Apparatus and method for securing a suture

ABSTRACT

A suture retainer has an upper or cover section and a lower or base section which cooperate to define passages through which portions of a suture extend. Projections on the cover section of the retainer extend into recesses on the base section of the retainer. A center projection on the base section extends between the two projections on the cover section. The projections cooperate with surfaces on body sections of the cover and base section of the retainer to position and grip portions of the suture. The retainer may be moved along the portions of the suture while the retainer is gripped by an applicator assembly. The applicator assembly is operable to apply energy to the retainer to bond end portions of the projections on the cover section to bottoms of recesses in the base section of the retainer.

BACKGROUND

[0001] The present invention relates to a new and improved apparatus andmethod which are used to secure a suture relative to body tissue.

[0002] It has previously been suggested that a retainer may be connectedwith a suture by applying energy to the retainer. The energy effects abonding of one portion of the retainer to another portion of theretainer. It has previously been suggested that a retainer could beconnected with a suture in the manner disclosed in Japanese laid-openPatent Application No. 8-140,982 and in U.S. Pat. Nos. 6,010,525;6,174,324; and 6,368,343.

SUMMARY OF THE INVENTION

[0003] The present invention relates to a new and improved apparatus andmethod for use in securing a suture. The suture is positioned relativeto sections of an improved retainer. The sections of the retainer areinterconnected when the retainer has been positioned relative to apatient's body tissue. The sections of the retainer may be bondedtogether by the application of energy to the retainer by an improvedapplicator assembly.

[0004] The improved retainer may have one or more projections whichengage one or more recesses to position the sections of the retainerrelative to each other. An interference fit may be provided between oneor more projections and one or more recesses to hold the sections of theretainer in a desired spatial relationship. The projections may havesurfaces which at least partially define one or more passages and guidemovement of one or more portions of the suture relative to the retainer.In addition, the surfaces on the projections may function to positionthe suture relative to the retainer.

[0005] The improved applicator assembly may be used to apply energy tothe retainer. Energy applied to the retainer may effect bonding of endportions of the projections to bottom portions of recesses in theretainer. The end portions of the projections may function as energydirectors which concentrate energy. If desired, one or more loops may beformed in the suture around one or more of the projections.

[0006] The applicator assembly may grip the retainer with apredetermined force. While the applicator assembly grips the retainer,the applicator assembly may be utilized to slide the retainer along thesuture to position the retainer relative to body tissue. While theapplicator assembly is gripping the retainer, the applicator assemblymay apply energy to the retainer to effect bonding of sections of theretainer together. The applicator assembly may be used to move theretainer into a cannula to engage tissue in a patient's body.

[0007] The present invention includes a plurality of different featureswhich may be utilized in combination with each other or separately. Thevarious features of the invention may be used in combination withfeatures of the prior art. For example, the improved retainer may beused with the improved applicator assembly or with a prior artapplicator assembly. As another example, the improved applicatorassembly may be used with the improved retainer or a prior art retainer.As still another example, the retainer may be moved through a cannula toa desired position relative to body tissue or may be positioned relativeto the body tissue without being moved through a cannula.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The foregoing and other features of the invention will becomemore apparent upon consideration of the following description taken inconnection with the accompanying drawings wherein:

[0009]FIG. 1. is a fragmentary schematic illustration depicting themanner in which a suture and an improved retainer are positionedrelative to body tissue;

[0010]FIG. 2. is an enlarged schematic pictorial illustration of theretainer of FIG. 1;

[0011]FIG. 3. is an exploded schematic pictorial illustration depictingthe construction of a base section and cover section of the retainer ofFIGS. 1 and 2;

[0012]FIG. 4. is an exploded schematic pictorial illustration, furtherillustrating the construction of the base and cover sections of theretainer;

[0013]FIG. 5. is an exploded schematic pictorial illustration, furtherillustrating the construction of the base and cover sections of theretainer;

[0014]FIG. 6. is an exploded schematic pictorial illustration furtherillustrating the construction of the base and cover sections of theretainer;

[0015]FIG. 7. is a schematic sectional view depicting the relationshipbetween the base and cover sections of the retainer of FIGS. 1-6 withportions of the suture disposed in passages in the retainer;

[0016]FIG. 8. is a schematic fragmentary sectional view, generallysimilar to FIG. 7, depicting the manner in which end portions ofprojections on the cover section of the retainer are bonded to bottomportions of recesses in the base section of the retainer;

[0017]FIG. 9. is a highly schematized sectional view illustrating theconstruction of an improved applicator assembly which is utilized tointerconnect sections of the retainer of FIGS. 1-7 in the mannerillustrated schematically in FIG. 8;

[0018]FIG. 10. is a schematic pictorial illustration of one embodimentof the applicator assembly of FIG. 9;

[0019]FIG. 11. is an enlarged fragmentary schematic pictorialillustration of a portion of the applicator assembly of FIG. 10,illustrating a trigger and spring housing;

[0020]FIG. 12. is an enlarged fragmentary schematic illustration of anend portion of the applicator assembly of FIG. 10;

[0021]FIG. 13. is a schematic illustration depicting the manner in whicha suture may be looped around projections on the retainer of FIGS. 1-8;

[0022]FIG. 14. is a schematic sectional view, generally similar to FIG.7 illustrating a second embodiment of the retainer;

[0023]FIG. 15. is a schematic illustration, taken generally along theline of 15-15 of FIG. 14, illustrating a relationship of the suture to acover section of the retainer;

[0024]FIG. 16. is a schematic illustration, generally similar to FIG.15, illustrating the manner in which the suture may be looped aroundprojections on the cover section of the retainer;

[0025]FIG. 17. is a schematic sectional view of another embodiment ofthe retainer;

[0026]FIG. 18. is a schematic sectional view of another embodiment ofthe retainer;

[0027]FIG. 19. is a schematic sectional view of another embodiment ofthe retainer;

[0028]FIG. 20. is a schematic plan view of another embodiment of theretainer;

[0029]FIG. 21. is a schematic sectional view, taken generally along theline 21-21 of FIG. 20, further illustrating the construction of theretainer;

[0030]FIG. 22. is a schematic sectional view of another embodiment ofthe retainer;

[0031]FIG. 23. is a schematic sectional view of another embodiment ofthe retainer;

[0032]FIG. 24. is a fragmentary schematic illustration depicting themanner in which the applicator assembly of FIGS. 9-12 may be utilized tomove the retainer of FIGS. 1-8 and 13-23 into a cannula; and

[0033]FIG. 25. is a fragmentary schematic illustration, generallysimilar to FIG. 12, depicting the manner in which a shield may beprovided on the distal portion of the applicator assembly of FIGS. 9-12.

DESCRIPTION OF SPECIFIC PREFERRED EMBODIMENTS OF THE INVENTION SUTURERETAINER

[0034] An improved retainer 30 is utilized to fixedly interconnectopposite portions 32 and 34 of a suture 36. The portions 32 and 34 ofthe suture 36 extend in opposite directions through the retainer 30. Anintermediate portion 38 of the suture extends between the portions 32and 34 and extends around body tissue 40 to the retainer 30. It shouldbe understood that the suture 36 and retainer 30 could be connected witheach other and/or the body tissue 40 in a manner which is different thanthe specific manner illustrated in FIG. 1. For example, the portions 32and 34 of the suture 36 may extend in the same direction from theretainer 30.

[0035] It is contemplated that the suture 36 and retainer 30 may beutilized to secure body tissue 40 in many different ways. For example,the suture 36 and retainer 30 may be utilized to secure one piece ofbody tissue to another piece of body tissue. The suture 36 and retainer30 may be utilized to secure soft body tissue to hard body tissue(bone). The suture 36 and retainer 30 may be utilized to connect hardbody tissue to hard body tissue in the manner disclosed in U.S. Pat. No.6,238,395. The suture 36 and retainer 30 may be disposed entirely withina patient's body or may engage a surface area on the patient's body.

[0036] It is contemplated that the suture 36 can be constructed of asingle filament or of a plurality of filaments. The suture 36 may beformed of biodegradable or nonbiodegradable material. Similarly, theretainer 30 may be formed of biodegradable or nonbiodegradable material.

[0037] It is believed that it may be desired to form the retainer 30from Poly-L-Lactic Acid (PLLA) or other resorbable polymer. Although itis believed that it may be desired to form the retainer 30 and suture 36of the same material, the retainer and suture may be formed of differentmaterials. For example, the suture 36 and retainer 30 may both be formedof a biodegradable material. Alternatively, one of the suture 36 andretainer 30 may be formed of a biodegradable material and the other oneformed of a nonbiodegradable material.

[0038] It is contemplated that the suture 36 and retainer 30 may bepositioned relative to the body tissue 40 using laproscopic orarthroscopic surgical procedures. The retainer 30 and suture 36 may bemoved into a patient's body through a cannula. Fiber optics may be usedin association with the cannula to facilitate positioning of the suture36 and retainer 30. The cannula may have any one of the constructionsdisclosed in U.S. Pat. Nos. 6,338,730 and 6,358,266. The positioning ofthe retainer 30 and suture 36 using endoscopic surgical procedures maybe preferred in order to minimize the size of an incision in a patient'sbody. Of course, the retainer 30 and suture 36 may be used with an openincision which is relatively large.

[0039] Regardless of whether the retainer 30 and suture 36 arepositioned in a patient's body using open or minimally invasive surgicaltechniques, it is contemplated that it may be desired to tension thesuture 36 with a predetermined force. A predetermined tension is appliedto the suture 36 by pulling the portions 32 and 34 of the suture fromthe retainer 30 with a predetermined force. The suture 36 is tensionedwith a force which is a function of the size and strength of the suture.

[0040] The manner in which the suture 36 is tensioned with apredetermined force may be the same as is disclosed in U.S. Pat. No.6,159,234 or in U.S. patent application Ser. No. 09/556,458 filed May 3,2000 by Peter M. Bonutti and entitled Method And Apparatus For SecuringTissue. The suture 36 is tensioned with a predetermined force by pullingthe portions 32 and 34 of the suture before securing the retainer 30 tothe suture to hold the suture. When the retainer 30 has been secured tothe suture 36 to hold the suture, the retainer grips the portions 32 and34 of the suture 36 to maintain a tension, corresponding to thepredetermined force, in the suture.

[0041] It is contemplated that a robotic mechanism may be utilized toposition the retainer 30 and/or suture 36 relative to the body tissue.An imaging device may be utilized in association with the roboticmechanism to facilitate positioning of the retainer 30 and suture 36relative to the body tissue. The robotic mechanism and/or imaging devicemay have any one of the constructions and be used in any one of the waysdisclosed in U.S. patent application Ser. No. 10/102,413 filed Mar. 20,2002 by Peter M. Bonutti and entitled Methods of Securing Body Tissue.During the surgery, the patient may be covered by a drapery system whichis connected with a surgeon so as to maintain a sterile field betweenthe surgeon and the patient in the manner disclosed in U.S. patentapplication Ser. No. 09/941,185 filed Aug. 28, 2001 by Peter M. Bonuttiand entitled Method of Performing Surgery. Of course, any desiredsterile drapery system may be provided to cover the patient.

[0042] In order to minimize the size of an incision in the patient, itis contemplated that minimally invasive surgical techniques disclosed inthe aforementioned U.S. patent application Ser. No. 09/941,185 filedAug. 28, 2001 by Peter M. Bonutti and entitled Method of PerformingSurgery may be utilized. It is believed that the utilization ofminimally invasive surgical techniques may be particularly advantageouswhen used in association with a robotic mechanism and/or imagingapparatus in the manner disclosed in U.S. patent Ser. No. 10/102,413filed Mar. 20, 2002 by Peter M. Bonutti. It is contemplated that amagnetic suturing system having a construction similar to that in U.S.patent application Ser. No. 10/005,652 filed by Peter M. Bonutti on Dec.3, 2001 and entitled Magnetic Suturing System and Method may be used toposition the suture 36.

[0043] The retainer 30 includes a lower or base section 46 (FIGS. 2 and3) and an upper or cover section 48. The portions 32 and 34 of thesuture 36 extend through passages 52 and 54 (FIGS. 2 and 7) formedbetween the upper and lower sections 46 and 48 of the retainer 30. Thepassages 52 and 54 have a cross sectional area which is slightly greaterthan the cross sectional area of the suture 36 (FIG. 7). Therefore, theportions 32 and 34 of the suture 36 can be readily pulled through thepassages 52 and 54 when the retainer 30 is in the initial or undeformedcondition illustrated in FIG. 7. It should be understood that thepassages 52 and 54 could have a configuration other than theconfiguration illustrated in FIG. 7.

[0044] Once the suture 36 has been tensioned with a desired force, theretainer 30 is plastically deformed in the manner illustratedschematically in FIG. 8. This results in the portions 32 and 34 of thesuture 36 being securely gripped between the lower and upper sections 46and 48 of the retainer 30. The portions 32 and 34 of the suture 36 aregripped with a clamping action which holds them against movementrelative to each other and to the retainer 30. This results in thedesired tension being maintained in the suture 36.

[0045] The lower section 46 of the retainer 30 includes a right (asviewed in FIG. 3) recess 58 and a left recess 60. The right and leftrecesses 58 and 60 have the same configuration and are disposed the samedistance from a central axis of the circular lower section 46 of theretainer 30. Although the recesses 58 and 60 could have many differentconfigurations, the illustrated recesses have elongated configurationswith parallel longitudinal central axes which extend perpendicular tothe central axis of the circular lower section 46.

[0046] The upper section 48 has a circular body 64 from which right (asviewed in FIG. 3) and left projections 66 and 68 extend. The right andleft projections 66 and 68 have the same cross sectional configurationwhich corresponds to the cross sectional configuration of the recesses58 and 60 (FIGS. 4, 5, 6, and 7). The projections 66 and 68 have anelongated configuration with parallel longitudinal central axes whichextend perpendicular the central axis of the circular body 64 of theupper section 48 of the retainer 30. The projections 66 and 68 aredisposed the same distance from a central axis of the upper section 48.It is contemplated that the projections 66 and 68 could have aconfiguration which is different than the specific configurationillustrated in FIGS. 4-7.

[0047] A center projection 72 is disposed on the lower section 46 of theretainer 30 at a location midway between the right and left recesses 58and 60 (FIGS. 3, 4 and 7). The left and right projections 66 and 68 onthe upper section 48 of the retainer 30 are telescopically received inthe right and left recesses 58 and 60 in the lower section 46 of theretainer 30 (FIGS. 2, 3, and 7). This results in the upper section 38 ofthe retainer being positioned in a coaxial relationship with the lowersection 36 of the retainer. The center projection 72 is disposed midwaybetween the right and left projections 66 and 68 when they engage theright and left recesses 58 and 60. The right and left recesses 58 and 60cooperate with the right and left projections 66 and 68 to orient theupper section of the retainer 48 with the longitudinal axes of the rightand left projections 66 and 68 extending parallel to the longitudinalaxis of the center section 72.

[0048] When the right and left projections 66 and 68 are disposed in theright and left recesses 58 and 60 (FIG. 7), the center projection 72cooperates with the right and left projections to partially form thepassages 52 and 54. The bottom (as viewed in FIG. 7) of the passage 52is formed by a gripper surface area 78. The bottom of the passage 54 isformed by a gripper surface area 80.

[0049] The gripper surface areas 78 and 80 on the lower section 46 faceand are parallel to gripper surface areas 82 and 84 (FIG. 7) on theupper section 48. The gripper surface areas 78, 80, 82 and 84 cooperatewith the projections 66, 68 and 72 to define the parallel passages 52and 54. The gripper surface areas 78, 80, 82 and 84 may be roughened orknurled to enhance their ability to grip the suture 36.

[0050] The right and left projections 66 and 68 have flat parallellongitudinally extending inner side surfaces 88 and 90 (FIGS. 4 and 7).The inner side surfaces 88 and 90 on the projections 66 and 68 extendperpendicular to the gripper surface areas 82 and 84 on the circularbody 64 of the upper section 48 of the retainer 30. In addition, theright and left projections 68 and 70 have outer side surfaces 92 and 94which extend parallel to the inner side surfaces 88 and 90.

[0051] The center projection 72 has parallel right and left sidesurfaces 96 and 98 which extend perpendicular to the gripper surfaceareas 78 and 80 on the lower section 46 (FIG. 4). When the right andleft projections 66 and 68 on the circular body 64 of the upper section48 of the retainer 30 are disposed in the right and left recesses 58 and60 on the lower section 46 (FIG. 7), the right and left side surfaces 96and 98 on the center projection 72 extend parallel to the inner sidesurfaces 88 and 90 on the right and left projections 66 and 68.

[0052] The passages 52 and 54 through the retainer 30 are formed by flatsurfaces on the lower and upper sections 46 and 48 of the retainer. Theflat side surfaces which form the parallel passages 52 and 54 areeffective to guide a leading end of a portion of a suture 36 as thesuture is inserted into the passage. Thus, the leading end of theportion 32 of the suture is directed by the side surfaces 78, 88, 82,and 98 (FIG. 7) formed on the lower section 46, right projection 66,body 64 and center projection 72 respectively. Similarly, the leadingend of the portion 34 of the suture 36 is directed by the side surfaces80, 90, 84 and 96 formed on the lower section 46, left projection 68,body 64 and center projection 72. By forming the passages 52 and 54 withelongated side surfaces, insertion of the portions 32 and 34 of thesuture 36 into the passages is facilitated. This is because once aportion 32 or 34 of the suture 36 has been inserted into one of thepassages 52 or 54, the side surfaces of the passage maintain the leadingend of the suture in a desired relationship with the passage as thesuture continues to be moved into the passage.

[0053] The center projection 72 is effective to position the portions 32and 34 of the suture 36 so that they are disposed on opposite sides ofand equal distances from a central axis of the retainer 30. This resultsin off setting movements being applied to the retainer 30 by forcestransmitted to the retainer from the portions 32 and 34 of the suture36. Therefore, there is little or no tendency for the retainer 30 torotate or flip relative to the body tissue 40.

[0054] The right and left projections 66 and 68 on the upper section 48of the retainer 30 are disposed in the recesses 58 and 60 in the lowersection 46 of the retainer 78 (FIG. 7) during insertion of the portions32 and 34 of the suture 36 into the passages 52 and 54 in the retainer30. To hold the projections 66 and 68 in the recesses 58 and 60, thereis an interference fit between the projections and the recesses. Thus,the distance between an outer side surface 102 of the right recess 58(FIG. 7) and an inner side surface 104 of the right recess is slightlyless than the distance between the outer side surface 92 and inner sidesurface 88 on the right projection 66. The resulting interferencebetween the right projection 66 and the right recess 58 is effective tohold the right projection in the right recess.

[0055] Similarly, the left recess 60 has parallel outer and inner sidesurfaces 110 and 112. The outer and inner side surfaces 110 and 112 ofthe left recess 60 are spaced apart by distance which is slightly lessthan the distance between the outer side surface 94 and inner sidesurface 90 on the left projection 68. When the left projection 68 ispressed into the left recess 60, the resulting interference between theside surfaces 90 and 94 on the projection 68 and the side surfaces 110and 112 on the recess 60 hold the left projection in the left recess.The side surfaces 102, 104, 110 and 112 on the recesses 58 and 60 extendparallel to the side surfaces 96 and 98 on the center projection 72 andperpendicular to the gripper surface areas 78 and 80 on the lowersection 46.

[0056] The interference fit between the projections 66 and 68 on theupper section 48 of the retainer with the recesses 58 and 60 in thelower section 46 of the retainer holds the two sections of the retaineragainst movement relative to each other during insertion of the portions32 and 34 of the suture 36 into the passages 52 and 54. However, it iscontemplated that the upper section 48 and lower section 46 of theretainer 30 may be held against movement relative to each other by meansother than an interference fit. For example, latch surfaces on theprojections 66 and 68 may engage latch surfaces formed on the sides ofthe recesses 58 and 60. These latch surfaces may have a generally wedgeshaped configuration. Alternatively, a pin may extend through at least aportion of the lower section 46 of the retainer and the projections 66and 68 on the upper section 48 of the retainer to hold the upper sectionagainst movement relative to the lower section.

[0057] The lower section 46 and upper section 48 of the retainer 30 areformed as two separate pieces. However, it is contemplated that thelower and upper sections 46 and 48 of the retainer 30 could be formed asone piece. If this is done, relatively weak connectors may be providedbetween the projections 66 and 68 and the base section 46 to hold thebase and upper sections 46 and 48 in a desired spatial relationship witheach other during insertion of the portions 32 and 34 of the suture 36into the passages 52 and 54. The weak connectors may be broken to enablethe portions 32 and 34 of the suture 36 to be gripped between theretainer sections 46 and 48. Alternatively, a flexible strap may beformed between the base section 46 and upper section 48. By deflectingthe strap, the projections 66 and 68 may be inserted into the recesses58 and 60.

[0058] When the right and left projections 66 and 68 are telescopicallyinserted into the right recess 58 and left recess 60, the leading orlower (as viewed in FIG. 7) end portions of the projections engage flatbottom surfaces 118 and 120 of the recesses 58 and 60 (FIG. 7). The flatbottom surfaces 118 and 120 extend parallel to the gripper surface areas78 and 80 on the lower section 46 and perpendicular to the side surfaces102, 104, 110 and 112 of the recesses 58 and 60. Engagement of endportions 124 and 126 of the projections 66 and 68 with the bottomsurfaces 118 and 120 of the recesses 58 and 60 positions the lower andupper sections 46 and 48 of the retainer relative to each other anddetermines the size of the passages 52 and 54. This results in thepassages 52 and 54 being sized so as to have a cross sectional areawhich is slightly greater than the cross sectional area of the portions32 and 34 of the suture 36 to enable the suture to be readily insertedinto the passages.

[0059] The center projection 72 has a flat upper side surface 130 whichextends parallel to the gripper surfaces 78, 80, 82 and 84. The upperside surface 130 on the center projection 72 is spaced from the uppersection 48 when the end portions 124 and 126 of the projections 66 and68 are in engagement with the bottom surfaces 118 and 120 of therecesses 58 and 60. However, if desired, the center projection 72 may bedisposed in engagement with the upper section 48 when the end portions124 and 126 of the projections 66 and 68 are in engagement with thebottom surfaces 118 and 120 of the recesses 58 and 60.

[0060] When the end portions 124 and 126 of the projections 66 and 68are in engagement with the bottom surfaces 118 and 120 of the recesses58 and 60, the portions 32 and 34 of the suture 36 can be freely movedin the passages 52 and 54 to enable the retainer 60 to be slid along thesuture 36 to a desired position relative to the body tissue 40. Theretainer 30 may be slid along the suture 36 under the influence of forcemanually applied against the retainer or under the influence of forceapplied against the retainer by a surgical instrument, such as forceps.As this occurs, the intermediate portion 38 (FIG. 1) of the suture istightened around the body tissue with a desired force.

[0061] Once the retainer 30 has been positioned in a desired locationrelative to the body tissue 40 and the suture 36 tensioned with apredetermined force, the retainer is plastically deformed from theinitial condition illustrated in FIG. 7 to the condition illustrated inFIG. 8. Plastic deformation of the retainer 30 results in the size ofthe passages 52 and 54 being decreased. In addition, the upper side 130on the center projection 72 moves into engagement with the upper section48 of the retainer 30. Engagement of the center projection 72 with theupper section 48 of the retainer 30 tends to limit the extent to whichthe lower and upper section 46 and 48 of the retainer are pressedtogether to thereby limit plastic deformation of the retainer 30.

[0062] If the retainer 30 is constructed so that the center projection72 engages the upper section 48 of the retainer when the end portions124 and 126 of the projections 66 and 68 are in engagement with thebottom surface areas 118 and 120 of the recesses 58 and 60, the centerprojection would also be deformed when the retainer is plasticallydeformed from the initial condition of FIG. 7 to the condition of FIG.8. With this construction of the retainer 30, the center projection 72would be deformed to the same extent as the projections 66 and 68.Therefore, the center projection 72 may be formed with an upper endportion which has the same configuration as the lower end portions 124and 126 of the projections 66 and 68.

[0063] To plastically deform and interconnect the lower and uppersections 46 and 48 of the retainer 30, a member 140 (FIG. 8) is movedinto a groove 142 in the lower section 46. In addition, a second member144 engages a flat outer side surface 146 on the upper section 48 of theretainer 30. The lower and upper sections 46 and 48 of the retainer 30are firmly pressed together by force transmitted between the members 140and 144 through the retainer. While the lower and upper sections 46 and48 of the retainer 30 are gripped between the members 140 and 144 with aclamping action, energy is transmitted from the member 144 to theretainer 30.

[0064] The energy applied to the retainer 30 is effective to heat theend portions 124 and 126 of the projections 66 and 68 into a transitiontemperature range for the polymeric material of the projections. Forceapplied against the retainer 30 by the members 140 and 144 (FIG. 8)causes the heat softened material of the projections 66 and 68 to flowin the recesses 58 and 60. To a lesser extent, material of the lowersection 46 is heated and also flows in the recesses 58 and 60.

[0065] As this occurs, the heated material of the projections 66 and 68may be forced upward toward the portions 32 and 34 of the suture 36. Theheated material tends to bond to the portions 32 and 34 of the suture 36it should be understood that the extent of deformation and flow of theheat softened material of the projections 66 and 68 may be and probablywill be greater than the extent illustrated schematically in FIG. 8.

[0066] If the retainer 30 is constructed so that the center projection72 is deformed to the same extent as the projections 66 and 68, heatsoftened material of the center projection would flow into the passages52 and 54. If the upper section 48 of the retainer 30 has theconstruction shown in FIG. 4, the upper end portion of the centerprojection would engage the flat lower side surface of the body 64.However, the upper section 48 of the retainer 30 may be formed with arecess to receive the upper end portion of the center projection 72.This recess may have the same configuration as the recesses 58 and 60 inthe lower section 46 of the retainer 30.

[0067] If desired, the retainer 30 may be constructed with the centerprojection 72 extending from the upper section 48 of the retainer. Ifthis is done, the center projection 72 from the upper section 48 of theretainer may have the same configuration as the illustratedconfiguration of the center projection in FIGS. 4 and 5. A recess may beprovided in the lower section 46 to receive a portion of a centerprojection from the upper section 48 of the retainer 30.

[0068] As the heated material of the projections 66 and 68 is caused toflow in the recess 58 and 60, the size of the passages 52 and 54 isdecreased. This results in the portions 32 and 34 of the suture 36 beingfirmly clamped between the gripper surface areas 78 and 80 on the lowersection 46 and the gripper surface areas 82 and 84 on the upper section48 of the retainer 30. The force applied to the portions 32 and 34 ofthe suture 36 by the gripper surface areas 78, 80, 82 and 84 on thelower and upper sections 46 and 48 of the retainer 30 is effective todeform the suture from the circular cross sectional configurationillustrated in FIG. 7 to a generally oval cross sectional configurationillustrated schematically in FIG. 8. Although the illustrated suture 36is a monofilament, it is contemplated that the suture could be formed bya plurality of filaments which are braided or twisted together.

[0069] The energy which is applied to the retainer 30 by the member 144may be thermal energy, vibratory energy, or light energy. The energy maybe transmitted by radio frequency waves, ultrasonic waves, heat waves,or light waves. The energy may be vibratory ultrasonic or radiofrequency energy. Rather than positioning the member 140 in the groove142 in the lower section 46 of the retainer 30, the groove 142 may beomitted and a flat member, similar to the member 144, may be pressedagainst the lower section 46 of the retainer 30. Energy may betransmitted to the retainer through either the member 140 or the member144 or both of the members 140 and 144.

[0070] In the embodiment of the invention illustrated in FIG. 8, theportions 32 and 34 of the suture 36 are clamped between the lowersection 46 and upper section 48 of the retainer 30. The clamping forceapplied against the portions 32 and 34 of the suture 36 by the retainer30, holds the retainer and the portions of the suture against relativemovement. This results in the suture 36 and retainer 30 being securelyinterconnected.

[0071] There is some bonding of material of the retainer to the portions32 and 34 of the suture 36 to further interconnect suture and theretainer. However, the amount of force and energy transmitted from themember 140 or both of the members 140 and 144 to the retainer 30 issufficient to effect a plastic deformation of the material of theretainer without excessive plastic deformation of the material of thesuture 36. By avoiding excessive deformation of the material of thesuture 36, weakening of the suture is avoided. Thus, once the plasticdeformation of the retainer 30 has been effected by the transmission offorce and energy to the retainer, the lower and upper sections 46 and 48of the retainer are fixedly interconnected with the suture 36 withoutsignificantly weakening of the suture.

[0072] The end portions 124 and 126 of the projections 66 and 68 have apointed configuration. Thus, the end portion 124 of the projection 66includes a flat side surface area 150 which intersects a flat sidesurface area 152 at a linear point or peak. Therefore, there is linecontact between the end portion 124 of the right projection 66 and theflat bottom surface 118 of the right recess 58. Similarly, the endportion 126 of the left projection 68 has a flat side surface 156 whichintersects a flat side surface 158 at a linear point or peak on the endportion 126 of the left projection 68. This results in line contactbetween the pointed end portion of the left projection 68 and the flatbottom surface 120 of the left recess 60. However, the end portions 124and 126 of the projections 66 and 68 may have a conical configuration ifdesired.

[0073] By forming the end portions 124 and 126 of the right and leftprojections 66 and 68 with a pointed configuration, the end portions ofthe projections are effective to function as energy directors forultrasonic vibratory energy. The pointed end portions 124 and 126 of theright and left projections 66 and 68 are effective to direct ultrasonicvibratory energy transmitted from the member 144 to the ends of theprojections and to the bottom surfaces 118 and 120 of the recesses 58and 60. The pointed configuration of the end portions 124 and 126 of theprojections 66 and 68 concentrates the energy and facilitates melting ofthe material of the projections. To a lesser extent, the material of thelower section 46 of the retainer 30 is melted adjacent to the bottomsurfaces 118 and 120. This results in a secure bonding andinterconnection between the lower and upper sections 46 and 48 of theretainer 30.

[0074] Applicator Assembly

[0075] An improved applicator assembly 172 (FIGS. 9-12) is utilized togrip the retainer 30 with a constant predetermined force, to move theretainer 30 along the suture 36 to a desired position relative to thebody tissue 40, and to transmit energy to the retainer 30. Theapplicator assembly 172 may be used to perform any one or more offoregoing functions rather than all of the functions.

[0076] The applicator assembly 172 includes a rigid energy transmissionmember 174 (FIG. 9) which corresponds to the member 144 in FIG. 8. Arigid tubular force transmitting member 176 extends around and iscoaxial with the cylindrical energy transmission member 174. Thecylindrical force transmitting member 176 corresponds to the member 140in FIG. 8.

[0077] A biasing assembly 178 continuously urges the force transmittingmember 176 toward the left (as viewed in FIG. 9) with a constantpredetermined force. The illustrated embodiment of the biasing assembly178 includes a helical spring 180 which is disposed between an annularflange 182 on a reaction member 184 and an annular piston 186. Theannular piston 186 is fixedly connected to a housing 188. The housing188 is connected to the tubular force transmitting member 176. Thereaction member 184 is fixedly connected to a manually engagable handle194.

[0078] A trigger 198 is pivotally connected with the handle 194. Thetrigger 198 is manually pivotal in a clockwise direction (as viewed inFIGS. 9 and 11). Clockwise pivotal movement of the trigger 198 transmitsforce through a yoke 200. The force transmitted through the yoke 200moves the housing 188 toward the right (as viewed in FIGS. 9 and 11).This rightward movement of the housing 188 moves a flange 204 on theright (as viewed in FIGS. 9 and 12) or distal end of the tubular forcetransmitting member 176 away from a circular end surface 206 on theenergy transmission member 174.

[0079] The rightward (as viewed in FIGS. 9 and 12) movement of the forcetransmitting member 176 relative to the energy transmission member 174increases space between the flange 204 and end surface 206 on the energytransmission member 174. Increasing the space between the flange 204 andthe end surface 206 enables the retainer 30 to be positioned between theflange 204 and the end surface 206 with the portions 32 and 34 of thesuture 36 extending through the passages 52 and 54 in the retainer 30 inthe manner illustrated in FIG. 7.

[0080] When the retainer 30 is positioned in the gap between the endsurface 206 (FIGS. 9 and 12) on the energy transmission member 174 andthe flange 204 connected with the force transmitting member 176, theflange 204 is positioned in the groove,142 in the retainer 30 in thesame manner as in which the member 140 is illustrated as engaging thegroove 142 in FIG. 8. The end surface 206 (FIGS. 9 and 12) on the energytransmission member 174 is disposed in engagement with the surface 146on the upper section 48 of the retainer 30 in the same manner as inwhich the member 144 (FIG. 8) engages the surface 146.

[0081] Once the retainer 30 has been positioned in the space between theflange 204 and the end surface 206 on the energy transmission member 174(FIGS. 9 and 12), the trigger 198 is released. When the trigger 198 isreleased, the biasing spring 180 is effected to urge the housing 188toward the left (as viewed in FIGS. 9 and 11). The leftward forceapplied by the spring 180 against the housing 188 is transmitted throughthe force transmitting member 176 and flange 204 to the retainer 30.This results in the retainer 30 being clamped between the flange 204 onthe force transmitting member 176 and end surface 206 on the energytransmission member 174. The spring 180 is effective to apply a constantpredetermined biasing force to the piston ring 186. This constantbiasing force is transmitted through the housing 188 and forcetransmitting member 176 to the retainer 30.

[0082] Prior to the transmission of energy to the retainer 30 throughthe energy transmission member 174, the force applied against theretainer 30 is ineffective to cause significant plastic deformation ofthe material of the retainer 30. At this time, the end portions 124 and126 (FIG. 7) of the right and left projections 66 and 68 are pressedagainst the bottom surfaces 118 and 120 of the recesses 58 and 60 with aconstant force. The portions 32 and 34 of the suture 36 are freelymovable in the passages 52 and 54.

[0083] While the retainer 30 is gripped with a predetermined constantforce by the applicator assembly 172, the retainer is moved to a desiredposition relative to the body tissue 40. To position the retainer 30relative to the body tissue, the surgeon holds the handle 194 of theapplicator assembly 172 in one hand and tensions the portions 32 and 34of the suture 36 with the other hand. The surgeon then manually appliesforce against the handle 194 to slide the retainer 30 along thetensioned portions 32 and 34 of the suture 36 toward the body tissue 40.The relatively long force transmitting member 176 and energytransmitting member 174 enable the applicator assembly 172 to move theretainer 30 through a small incision to a remote location in a patient'sbody as the retainer slides along the suture 36.

[0084] During performance of a surgical procedure, the suture 36 may bemoved through a cannula to a location disposed within a patient's body.The suture 36 is then positioned relative to the tissue 40 at the remotelocation in the patient's body. However, it should be understood thatthe cannula may be omitted and the suture 36 moved through an openincision.

[0085] Once the suture 36 has been moved to the desired locationrelative to the tissue 40 in the patient's body, the portions 32 and 34of the suture may be positioned in the passages 52 and 54 through theretainer while the retainer is disposed outside of the patient's body.Once the portions 32 and 34 of the suture 36 have been positioned in thepassages 52 and 54 to the retainer 30, the retainer is gripped by theapplicator assembly 172. The flange 204 on the force transmitting member176 and end surface 206 on the energy transmission member 174 of theapplicator assembly 172 are effective to apply a predetermined constantforce against opposite sides-of the retainer 30 to securely grip theretainer with the applicator assembly 172.

[0086] While the retainer is gripped by the applicator assembly 172, theend portions 32 and 34 of the suture are manually tensioned and theretainer is slid along the portions 32 and 34 of the suture toward thebody tissue. As the retainer 30 is slid along the suture 36 toward thebody tissue 40, the applicator assembly 172 moves the retainer into thepatient's body. As the retainer 30 is moved into the patient's body, itis gripped with a constant predetermined force by the applicatorassembly 172.

[0087] Alternatively, the retainer 30 may be gripped by the applicatorassembly 172 outside of the patient's body prior to insertion of theportions 32 and 34 of the suture through the passages 52 and 54. Theportions 32 and 34 of the suture 36 may then be inserted through thepassages 52 and 54 in the retainer 30 while the retainer is gripped bythe applicator assembly 172. If desired, insertion of the portions 32and 34 of the suture 36 through the passages 52 and 54 in the retainer30 may be performed with the retainer inside the patient's body.

[0088] If the applicator assembly 172 is utilized to move the retainer30 through a cannula into the patient's body before the suture 36 isinserted into the passages 52 and 54 through the retainer, suitableinstruments may be utilized to grip the portions 32 and 34 of the suturein the patient's body and to move the portions 32 and 34 of the suturethrough the passages 52 and 54. The instruments which engage the sutureand move it through the passages 52 and 54 while the retainer 40 isgripped by the applicator assembly 172, may extend through the cannulaalong with the applicator assembly. Alternatively, the instruments whichmove the portions 32 and 34 of the suture 36 through the passages 52 and54 may be moved into the patient's body through a cannula spaced fromthe cannula through which the applicator assembly 172 moves the retainerinto the patient's body. In order to minimize incisions in the patient'sbody, it may be preferred to utilize a single cannula to accommodatemovement of the applicator assembly 172, retainer 30, suture positioninginstruments, and the suture 36 into the patient's body.

[0089] It is contemplated that it may be desired to position the suture36 and retainer 30 in a patient's body with a robotic mechanism. Whenthis is to be done, the manually engagable handle 194 and trigger 198 onthe applicator assembly 172 may be eliminated. The remainder of theapplicator assembly may then be connected with the robotic mechanism. Asuitable motor may be provided in the robotic mechanism to move theforce transmitting member 176 against the influence of the biasingspring 180. Even though the handle 194 and trigger 198 are eliminated,the retainer 30 would be gripped between the flange 204 on the forcetransmitting member 176 and end surface 206 on the energy transmissionmember 174 with a constant force.

[0090] The robotic mechanism with which the applicator assembly 172 isconnected may have a plurality of adaptive arms which are effective tomove the retainer 30 and other instruments in a patient's body. Therobotic mechanism may be a reprogrammable, multifunctional manipulatordesigned to move through various program motions for the performance ofselected one of a plurality of surgical procedures. The roboticmechanism may have manually operable controls which provide forinteraction between a surgeon and the robotic mechanism. The roboticmechanism may have any one of many different constructions and may beoperated in any one of many different manners, including those disclosedin U.S. patent application Ser. No. 10/102,413 filed Mar. 20, 2002 byPeter M. Bonutti and entitled Methods of Securing Body Tissue.

[0091] When the applicator assembly 172 is to be utilized in associationwith a robotic mechanism, it is believed that it may be desired toutilize a monitor or display in association with the robotic mechanism.A single imaging device or a plurality of imaging devices may be used.If a plurality of imaging devices are used, it is contemplated thatstereoscopic and/or video stereoscopic viewing at a location where asurgical procedure is being performed may be accommodated by the imagingapparatus. The imaging apparatus may include a plurality of endoscopes.

[0092] A navigation system may be utilized to provide inputs to thecomputer to assist in the control of the robotic mechanism and theperformance of a surgical procedure. The navigation system may be anoptical navigation system in which end portions of navigation membersare illuminated by light. The navigation members may be connected withone or more tissues in a patient's body. The tissue with which thenavigation members are connected may either bone or soft tissue.

[0093] It is also contemplated that imaging devices such as afluoroscope, and/or magnetic resonance imaging unit and/or ultrasonicimaging unit may be utilized with the robotic mechanism. If desired,endoscopes may be utilized in association with the various imagingunits. The imaging units and robotic mechanisms may have a constructionand cooperate with each other in the same manner as described in theaforementioned U.S. patent application Ser. No. 10/102,413 filed Mar.20, 2002 by Peter M. Bonutti.

[0094] Once the retainer 30 has been positioned in a desiredrelationship with body tissue 40 and the suture 36, the portions 32 and34 of the suture 36 are pulled with a predetermined force. This resultsin a predetermined tension being established in the portions 32 and 34of the suture 36. While the predetermined tension is maintained in thesuture 36, the retainer 30 is plastically deformed to connect theretainer with the portions 32 and 34 of the suture 36 and hold theportions 32 and 34 of the suture against movement relative to each otherand the retainer 30. To effect plastic deformation of the retainer 30and connection of the retainer with the suture 36, energy is transmittedfrom an energy source 212 (FIG. 9) through the energy transmissionmember 174 to the retainer 30. At this time, the retainer 30 is clampedbetween the flange 204 on the force transmitting member 176 and the endsurface 206 on the energy transmission member 174.

[0095] In the illustrated embodiment of the applicator assembly 172, theenergy source 212 is a source of ultrasonic vibratory energy at afrequency above that which can normally be detected by the human ear,that is about 16 to 20 kilohertz. Although there are a wide range offrequencies which may be utilized, it is believed that it may bedesirable to use ultrasonic energy having a frequency of between 20kilohertz and 70 kilohertz. It is believed that it may be desired to useultrasonic vibratory energy of a frequency between 39.5 and 41kilohertz. When a foot pedal actuated switch 214 (FIG. 9) is closed,ultrasonic vibratory energy is transmitted through the energytransmission member 174 to the retainer 30. The ultrasonic vibratoryenergy creates frictional heat at the pointed end portions 124 and 126of the projections 66 and 68. The frictional heat provided by theultrasonic vibratory energy is effective to heat material of the sutureretainer 30 into its transition temperature range while the material ofthe suture 36 remains at a temperature below its transition temperaturerange. For example, the suture 36 may be formed of a material having atransition temperature range which is above 190 degrees Celsius. Thesuture retainer 40 may have a transition temperature range which beginsat a temperature below 190 degrees Celsius.

[0096] However, it should be understood that even the entire transitiontemperature range for the suture 36 could be co-extensive with thetransition temperature range for the retainer 30. In fact, thetransition temperature range of the suture 36 could extend below thetransition temperature range of the retainer 30. However, it is believedthat it may be preferred to have the transition temperature range forthe suture 36 above at least a portion of the transition temperaturerange of the retainer 30.

[0097] Ultrasonic vibratory energy is transmitted from the energytransmission member 174 to the upper section 48 of the retainer 30. Theright and left projections 66 and 68 (FIG. 7) from the upper section 48of the retainer 30 function as energy directors which direct theultrasonic vibratory energy to the locations where the end portions 124and 126 of the projections 66 and 68 engage the bottom surfaces 118 and120 of the recesses 58 and 60 in the lower section 46 of the retainer30. The pointed end portions 124 and 126 of the projections 66 and 68concentrate the vibratory energy transmitted through the energytransmission member 174 at the locations where the projections engagethe bottom surfaces 118 and 120 of the recesses 58 and 60.

[0098] The ultrasonic vibratory energy is effective to soften and makethe material forming the end portions 124 and 126 of the projections 66and 68 flowable under the influence of the constant predetermined forcetransmitted from the biasing spring 180 through the force transmissionmember 176 and flange 204 to the lower section 46 of the retainer 30. Asthe temperature of the end portions 124 and 126 of the projections 66and 68 increases, the lower section 46 of the retainer 30 moves towardthe upper section 48 of the retainer. This results in material whichoriginally formed the pointed end portions 124 and 126 of theprojections 66 and 68 being deflected sideways in the lower (as viewedin FIG. 7) portions of the recesses 58 and 60.

[0099] The continued application of a constant clamping force to theretainer 30 and the transmission of vibratory energy to the retainercauses the end surface 130 on the center projection 72 to move intoengagement with the circular body 64 of the upper section 48. There maybe a limited heating, melting and deformation of the center projection72 as a result of engagement of the center projection with the uppersection 48.

[0100] Although it is believed that it will be preferred to applyultrasonic vibratory energy to the retainer 30, other forms of energymay be applied to the retainer if desired. For example, thermal or light(laser) energy may be applied to the retainer if desired. The energyapplication apparatus may be separate from the apparatus which is usedto position the retainer relative to the body tissue 40 and suture 36.Thus, the retainer 30 may be positioned relative to body tissue 40 andthe suture 36 manually or by using a first apparatus. Energy may then beapplied to the retainer 30 using a second apparatus.

[0101] The heated, flowable material of the end portions 124 and 126 ofthe projections 66 and 68 may flow along the side surfaces 102, 104, 110and 112 of the recesses 58 and 60. Some of the material of the endportions 124 and 126 of the projections 66 and 68 may engage and bond tothe portions 32 and 34 of the suture 36.

[0102] At the same time, the portions 32 and 34 of the suture 36 aredeflected from their original circular configuration (FIG. 7) to an ovalconfiguration under the influence of force applied against the portionsof the suture disposed between the lower section 46 and upper section 48of the retainer 30. Although the portions 32 and 34 of the suture 36 areresiliently deflected to the configuration illustrated schematically inFIG. 8, there is minimal bonding of the material with the retainer 30 tothe suture 36 and no significant loss of strength of the suture. Due tothe clamping action between the flange 204 and end surface 206 on theenergy transmission member 174 (FIG. 9) against the retainer 30, theoverall height of the retainer is decreased. At the same time, theoverall diameter of the retainer increases.

[0103] When the transmission of ultrasonic vibratory energy through theenergy transmission member 174 is interrupted, the material of theretainer 30 cools and there is an ultrasonic welding of the lowersection 46 of the retainer to the upper section 48 of the retainer. Thebonding between the lower section 46 and upper section 48 of theretainer 30 occurs mainly between the projections 66 and 68 and thelower section 48 of the retainer. There may be some bonding of thecenter projection 130 to the circular body 64 of the upper section 48 ofthe retainer. In addition, there may be some bonding material of thelower section 46 and upper section 48 of the retainer to the portions 32and 34 of the suture 36.

[0104] The portions 32 and 34 of the suture 36 are held against movementrelative to each other and to the retainer primarily 30 by a clampingaction between surfaces on the lower section 46 and surfaces on theupper section 48 of the retainer. Thus, the portions 32 and 34 of thesuture 36 are securely gripped between the gripper surface areas 78 and80 on the lower section 46 of the retainer 30 and the gripper surfaceareas 82 and 84 on the upper section 48 of the retainer 30. By holdingthe portions 32 and 34 of the suture 36 against movement relative toeach other and to the retainer 30 with a clamping action, there isminimal deformation of the suture and the strength of the suture is notimpaired.

[0105] Although one specific preferred embodiment of the applicatorassembly 172 has been illustrated in FIGS. 10-12, it is contemplatedthat the applicator assembly could have a different construction and/ormode of operation. For example, the applicator assembly 172 may have anyone of the constructions and mode of operations disclosed in U.S. patentapplication Ser. No. 10/076,919 filed Feb. 15, 2002 by Peter M. Bonutti,et al and entitled Method of Using Ultrasonic Vibration to Secure BodyTissue. Although it is believed that a retainer having a constructionsimilar to that illustrated in FIGS. 1-8 may be preferred, it iscontemplated that the applicator assembly 172 of FIGS. 9-12 may beutilized with retainers having a different construction. For example,the applicator assembly 172 may be utilized in association with aretainer having any one of the constructions disclosed in theaforementioned U.S. patent application Ser. No. 10/076,919 filed Feb.15, 2002 by Peter M. Bonutti or any one of the constructions disclosedin U.S. Pat. No. 6,010,525.

[0106] The leading end portion of the force transmitting member 176(FIG. 12) extends part way around the end surface 206 on the energytransmission member 174. This results in the formation of a shield 220which extends part way around the retainer 30 when the retainer 30 isclamped between the flange 204 and the end surface 206 on the energytransmission member 174. The shield 220 has an inner side surface 222which forms a portion of a cylinder. The side surface 222 engages thecylindrical periphery of the retainer 30 to position the retainerrelative to the energy transmission member 174 in a direction transverseto a longitudinal central axis of the energy transmission member.

[0107] The shield 220 is effective to at least partially blockengagement of body tissue with the retainer 30 as the retainer ispositioned in a patient's body and as energy is transmitted to theretainer from the energy transmission member 174. It is contemplatedthat the shield 220 could be constructed in such a manner as to extendcompletely around the retainer 30. This would allow use of theapplicator assembly 172 in a moist environment or in an aqueousenvironment in which the retainer is completely or almost completelysubmerged in liquid.

[0108] The force transmitting member 176 has a flange 204 which engagesthe groove 142 in the same manner as which the member 140 isschematically depicted as engaging a groove 142 in FIG. 8. However, itis contemplated that the flange 204 could be eliminated and a circularend plate provided at the distal end of the force transmitting member176. The use of a plate would provide for a wider area of engagement ofthe force transmitting member 176 with the lower section 46 of theretainer 30. The use of a circular end plate in place of the flange 204would allow the groove 142 in the lower section 46 of the retainer to beeliminated.

[0109] Prior to connecting the retainer 30 with the suture 36, theportions 32 and 34 of the suture are pulled with a predeterminedtension. Tensioning the suture with a predetermined force may beaccomplished in the manner disclosed in the aforementioned U.S. patentapplication Ser. No. 09/556,458 filed May 3, 2000 by Peter M. Bonuttiand entitled Method and Apparatus For Securing Tissue or in the mannerdisclosed in U.S. patent application Ser. No. 10/102,413 filed Mar. 20,2002 by Peter M. Bonutti and entitled Methods of Securing Body Tissue.Once a desired tension has been established in the intermediate portion38 (FIG. 1) of the suture 36, the applicator assembly 172 is utilized tointerconnect the lower section 46 and upper section 48 of the retainerin the manner previously discussed.

[0110] Since the portions 32 and 34 of the suture 36 were positioned inthe passages 52 and 54 on opposite sides of the center projection 72,the portion 32 of the suture applies force against the lower section 46of the retainer on the right (as viewed in FIG. 7) side of the centralaxis of the retainer. The portion 34 of the suture applies force againstthe lower section 46 of the retainer on the left side of the centerprojection 72. This results in the application of offsetting movementsto the lower section 46 of the retainer. Therefore, the retainer 30 doesnot tend to rotate on an axis disposed between the portions 32 and 34 ofthe suture 36 and is stable relative to the body tissue 40.

[0111] Although it is believed that it may be desired to use theapplicator assembly 172 to position the retainer 30 relative to bodytissue, it should be understood that other ways of positioning theretainer elative to body tissue may be utilized. For example, a surgeonmay grasp the retainer 30 with one hand and tension the portions 32 and34 of the suture 36 with the other hand. The surgeon would then manuallyapply force against the retainer 30 to slide the retainer along thetensioned portions 32 and 34 of the suture toward the body tissue.Rather than gripping the retainer 30 with one hand, the surgeon may gripthe retainer 30 with a manually actuated instrument.

[0112] If the retainer 30 is manually positioned relative to body tissueor positioned with a manually actuated instrument, a source of energywill have to be provided to interconnect the sections 46 and 48 of theretainer. The energy source may have any of the constructions disclosedin U.S. Pat. No. 6,368,343. Alternatively, the energy source may havethe construction disclosed in U.S. Pat. No. 3,513,848.

[0113] Looped Suture

[0114] In FIGS. 1-8, the portions 34 and 36 of the suture extendstraight through the retainer 30 in a generally parallel relationshipwith each other. However, it is contemplated that the portions 34 and 36of the suture may be looped around portions of the retainer to increasethe strength of the connection between the suture 36 and the retainer30. In the embodiment of FIG. 13, the suture is looped around theprojections 66 and 68 from the upper section 48 of the retainer. Bylooping the portions 32 and 34 of the suture around the projections 66and 68, in the manner illustrated in FIG. 13, the strength of the gripwhich the retainer 30 obtains on the suture is increased.

[0115] When the suture 36 is to be positioned relative to the retainer30 and looped around the projections 66 and 68, in the mannerillustrated schematically in FIG. 13, the portion 32 of the suture isinserted through the passage 52 between the right projection 66 from theupper section 48 of the retainer. The portion 32 of the suture is thenwrapped around the projection 66 and again inserted through the passage52 to form a loop around the projection 66. The portion 34 of the suture36 is looped around the projection 68 from the upper section 48 of theretainer 30 in the same manner as in which the portion 32 of the sutureis looped around the projection 66.

[0116] As was previously mentioned, the portions 32 and 34 of the suture36 are moved in opposite directions into the retainer 30. Thus, when theportion 32 of the suture 36 is initially moved through the passage 52,the suture is moved downward (as viewed in FIG. 13) through the passageand then wrapped upwardly around the projection 66 in a counterclockwise direction (as viewed in FIG. 13) and again moved downwardthrough the passage 52. When the portion 34 of the suture is to bepositioned in the passage 54 in the retainer 30, the portion 34 of thesuture is first moved upward (as viewed in FIG. 13) through the passage54 and then wrapped in a counter clockwise direction about theprojection 68. As the portion 34 of the suture is wrapped around theprojection 68, the portion 34 of the suture is again inserted throughthe passage 54. This results in the formation of a loop 232 around theprojection 68. The intermediate portion 38 of the suture 36 extendsupward (as viewed in FIG. 13) from the loop 230 and extends downward (asviewed in FIG. 13) from the loop 232.

[0117] Once the loops 230 and 232 have been formed in the portions 32and 34 of the suture 36, the retainer 30 is gripped by the applicatorassembly 172 and moved along the suture 36 toward the body tissue in themanner previously discussed. Movement of the retainer along the suture36 toward the body tissue will, to some extent, be impeded by the loops230 and 232 in the suture 36. By applying force with a handle 194 of theapplicator assembly 172, the retainer 30 can be moved along the suture36 toward the body tissue after the loops 230 and 232 have been formedin the suture 36. It should be understood that the retainer 30 may bemanually moved along the suture 36 or moved along the suture with anapplicator assembly having a construction which is different than theconstruction of the applicator assembly 172.

[0118] Although the loops 230 and 232 have been illustrated as beingformed around the projections 66 and 68 from the upper section 48 of theretainer 30, it is contemplated that the loops could be formed around adifferent portion of the retainer 30 if desired. For example, one orboth of the loops 230 and 232 could be formed around the centerprojection 72.

[0119] Alternatively, both of the loops 230 and 232 could be formedaround both of the projections 66 and 68. When this is to be done, theportion 32 of the suture 36 would be moved downward (as viewed in FIG.13) through the passage 52 and looped around the outside of theprojection 66 across the upper (as viewed in FIG. 13) end portion of thecenter projection 72 and downward around the left projection 68, acrossthe bottom (as viewed in FIG. 13) of the center projection 72 and againwrapped around the outside of the right projection 66. The portion 32 ofthe suture 36 would then be moved downward for a second time, throughthe passage 52. Similarly, the portion 34 of the suture 36 is movedupward (as viewed in FIG. 13) through the passage 54, downward aroundthe left projection 68, across the lower (as viewed in FIG. 13) end ofthe center projection 72 upward around the outside of the rightprojection 66. The loop would then be moved across the upper end portionof the center projection 72 and downward (as viewed in FIG. 13) for asecond time across the outside of the left projection 68. The portion 34of the suture 36 would then again be moved upward through the passage54.

[0120] Embodiment of FIGS. 14-16

[0121] In the embodiment of the retainer illustrated in FIGS. 1-8, theretainer 30 has a center projection 72 which cooperates with the rightand left projections 66 and 68 to form the two elongated passagesthrough which the portions 32 and 34 of the suture are moved in oppositedirections. In the embodiment of the invention illustrated in FIGS.14-16, the center projection on the retainer is omitted. Since theembodiment of the invention illustrated in FIGS. 14-16 is generallysimilar to the embodiment of the invention illustrated in FIGS. 1-8,similar numerals will be utilized to identify similar components, thesuffix “a” being associated with the numerals of FIGS. 14-16 to avoidconfusion.

[0122] A retainer 30 a includes a lower section 46 a and an uppersection 48 a. The lower section 46 a has a pair of recesses 58 a and 60a. The recesses 58 a and 60 a have the configuration as the recesses 58and 60 of FIGS. 1-8. Right and left projections 66 a and 68 a extenddownward (as viewed in FIG. 14) from the upper section 48 a into therecesses 58 a and 60 a in the lower section 60 a. There is aninterference fit between the projections 66 a and 68 a and the recesses58 a and 60 a to hold the upper section 48 a in a desired spatialrelationship with the lower section 46 a of the retainer 30 a. In theembodiment of the invention illustrated in FIG. 15, the portions 32 aand 34 a of the suture 36 a are disposed in a side-by-side relationshipin a single passage 240 (FIG. 14) which extends between projections 66 aand 68 a from the portion 48 a of the retainer 30 a.

[0123] When the retainer 30 a is gripped by the applicator assembly 172with a constant predetermined force, end portions 124 a and 126 a (FIG.14) of the projections 66 a and 68 a are pressed against bottom surfacesof the recesses 58 a and 60 a in the manner previously described inconjunction with the embodiment of the invention illustrated in FIGS.1-8. The projections 66 a and 68 a have the same configuration as theprojections 66 and 68 of FIGS. 3-7. Therefore, there is line contactbetween the tapered end portions 124 a and 126 a of the projections 66 aand 68 a and the flat bottom surfaces of the recesses 58 a and 60 a.

[0124] The portions 32 a and 34 a of the suture 36 a are inserted inopposite directions through the passage 240 formed between the lowersection 46 a and upper section 48 a of the retainer 30 a. The retainer30 a is slid along the suture 36 a to a desired position relative tobody tissue while the retainer is gripped with a constant predeterminedforce by the applicator assembly 172. If desired, the retainer 30 a maybe manually gripped and slid along the portions 32 a and 34 a of thesuture 36 a.

[0125] If the retainer 30 a is manually positioned relative to bodytissue, a suitable source of energy will have to be provided to effectheating of the retainer. This source of energy may have any one of theconstructions disclosed in U.S. Pat. Nos. 3,513,848 and 6,368,343.Alternatively, the source of energy may have a known construction and bea source of thermal in light (laser) energy.

[0126] Assuming that the applicator assembly 172 is utilized to positionthe retainer 30, when the foot pedal actuated switch 214 (FIG. 9) isclosed, ultrasonic vibratory energy is transmitted from the source 212through the energy transmission member 174 to the retainer 30 a (FIG.14). The tapered end portions 124 a and 126 a of the projections 66 aand 68 a function as energy directors and concentrate the ultrasonicvibratory energy from the source 212. As this occurs, the end portions124 a and 126 a of the projections 66 a and 68 a are softened anddeformed under the influence of the constant predetermined force appliedagainst the retainer 30 a by the applicator assembly 172 As this occurs,the distance between the lower section 46 a and upper section 48 a isdecreased and the portions 32 a and 34 a of the suture 36 a are grippedbetween flat gripper surfaces 242 and 244 formed on the upper section 48a and lower section 46 a of the retainer 30 a.

[0127] In FIG. 15, the portions 32 a and 34 a of the suture 36 a extendstraight through the passage in opposite directions. In the embodimentillustrated in FIG. 16, the portions 32 a and 34 a of the suture arelooped around the projections 66 a and 68 a in the same manner aspreviously described in conjunction with FIG. 13. This results in theformation of loops 230 a and 232 a around the projections 66 a and 68 a.By wrapping the portions 32 a and 34 a of the suture 36 a around theprojections 66 a and. 68 a, the portions 32 a and 34 a are positioned inthe passage 240 at locations equal distances from the center of theretainer 30 a. This minimizes any movement resulting from forces appliedto the retainer 30 a by the suture 36 a and increases the stability ofthe retainer on the body tissue.

[0128] In the embodiment of the invention illustrated in FIGS. 1-8 and14-16, the lower section 46 is provided with recesses 58 and 60.However, it is contemplated that the recesses 58 and 60 may be omittedif desired. If the recesses 58 and 60 are omitted, the projections 66and 68 (FIGS. 7 and 8) will engage a flat upper side surface on the basesection 46. With this construction, the pointed end portions 124 a and126 a (FIG. 14) of the projections 66 a and 68 a will engage a flatsurface 244 on the base section, 46 a.

[0129] When the recesses 58 and 60 are omitted, it may be desired toprovide other structure to maintain the lower and upper sections 46 and48 of the retainer in a desired spatial relationship during insertion ofthe suture 36 into a passage 24 or passages 52 and 54. For example, thecenter projection 72 (FIG. 3) may extend into an opening through theupper section 48. An interference fit may be provided between the centerprojection and the opening in the upper section 48. Alternatively, aguide surface connected with the lower section 46 of the retainer mayengage a guide surface on the upper section 48.

[0130] Embodiment of FIG. 17

[0131] In the embodiments of the invention illustrated in FIGS. 1-8 and14-16, a plurality of projections from the upper section 48 engagerecesses in the lower section 46. In the embodiment of the illustratedin FIG. 17, a single projection from the upper section engages an upperside of the lower section. Since the embodiment of the inventionillustrated in FIG. 17 is generally similar to the embodiments of theinvention illustrated in FIGS. 1-8 and 14-16, similar numerals will beutilized to identify similar components, the suffix letter “b” beingadded to the numerals of FIG. 17 to avoid confusion.

[0132] A retainer 30 b includes a lower or base section 46 b and anupper or cover section 48 b. A right passage 250 and a left passage 252are formed in the lower section 46 b. Similarly, a right passage 256 anda left passage 258 are formed in the upper section 48 b. A suture 36 bextends through the passages 250, 252, 256 and 258 in the lower andupper sections 46 b and 48 b of the retainer 30 b. The suture 36 bincludes end portions 32 b and 34 b which are interconnected by anintermediate portion 38 b. The intermediate portion 38 b of the suture36 b extends around body tissue in much the same manner as isillustrated schematically in FIG. 1 for the suture 36.

[0133] A single projection 262 extends from the upper section 48 b ofthe retainer 30 b. The projection 262 is offset to one side of thesuture 36 b. The projection 262 has a pointed end portion 264 which isengagable with a flat upper side surface 266 on the lower portion 46 bof the retainer 30 b. The pointed end portion 264 of the projection 262has the same general configuration as the pointed end portions 124 and126 of the projections 66 and 68 in FIG. 7. However, the pointed endportion 264 of the projection 262 may have a conical configuration ifdesired.

[0134] If desired, a pair of projections, corresponding to theprojections 66 and 68, may be provided. If this is done, one of theprojections would be offset from the suture 36 b in a direction into thepage on which FIG. 17 is disposed and the other projection would beoffset from the suture 36 b in a direction out of the page on which FIG.17 is disposed. This would result in a passage being formed between thetwo projections so that the portions 32 b and 34 b of the suture 36 bwould both extend through a passage between the projections.

[0135] When the suture 36 b and retainer 30 b are to be connected withbody tissue, the suture may be positioned relative to the body tissue inthe manner previously described in conjunction with in the embodiment ofthe invention illustrated in FIGS. 1-8. As was previously mentioned,this may be done using minimally invasive surgical techniques. Thesuture 36 b may be moved into a patient's body through a cannula andpositioned relative to tissue in the patient's body. The end portions 32b and 34 b of the suture may extend through the cannula and beaccessible to a surgeon.

[0136] The portion 32 b of the suture 36 b is inserted through thenonlinear passage 250 in the lower section 46 b and through thenonlinear passage 258 in the upper section 48 b of the retainer 30 b.The portion 34 b of the suture is inserted through the nonlinear passage252 in the lower portion 46 b and through the nonlinear passage 256 inthe upper portion 48 b, in the manner indicated schematically in FIG.17. The lower section 46 b and upper section 48 b are then gripped by anapplicator assembly which may have the same construction as theapplicator assembly 172 of FIGS. 9-12.

[0137] While the retainer 30 b is gripped with a constant predeterminedforce by the applicator assembly 172, the surgeon grips the applicatorassembly with one hand and the portions 32 b and 34 b of the suture 36 bwith the other hand. The retainer 30 b is then slid along the suture 36b toward the body tissue around which the intermediate portion 38 b ofthe suture extends. As this occurs, the end portion (FIG. 12) of theapplicator assembly 172 moves through the cannula and slides theretainer 30 b along the suture 36 b to a position that is engagementwith the body tissue, that is, to a position similar to that in FIG. 1for the retainer 30. While the retainer 30 b is being slid along thesuture 36 b, the applicator assembly grips the retainer with a constantpredetermined force.

[0138] If desired, the retainer 30 b may be positioned relative to thesuture 36 b and body tissue in a way other than use of the applicatorassembly 172. For example, the retainer 30 b may be gripped by one handof a surgeon and the portions 32 b and 34 b of the suture gripped andtensioned with the other hand. The manual application of force to theretainer 30 b would slide the retainer along the suture 36 b.

[0139] Once the retainer 30 b has been positioned relative to the bodytissue and the suture 36 b is tensioned with a desired force, energy isconducted from a source of energy, similar to the energy source 212 ofFIG. 9, to the energy transmission member 174 and the retainer 30 b. Itis contemplated that many different types of energy could be transmittedto the retainer 30 b. For example, radio frequency, ultrasonic, heat, orlight energy may be transmitted to the retainer 30 b through an energytransmission member. In the embodiment of the applicator assembly 172illustrated in FIGS. 9-12, ultrasonic vibratory energy is conducted tothe retainer 30 b through the energy transmission member 174 while theapplicator assembly 172 grips the retainer 30 b with a constantpredetermined force.

[0140] The projection 262 functions as an energy director whichconcentrates energy applied to the upper section 48 of the retainer 30 bby the end surface 206 of the energy transmission member 174 (FIG. 9).The concentrated ultrasonic vibratory energy transmitted from the energytransmission member 174 heats the material of the projection 262 (FIG.17) and the material of the base section 46 b engaged by the projectioninto its transition temperature range. As this occurs, there is asoftening and deforming of the material of the projection 262.

[0141] A flat lower side surface 270 on the upper portion 48 b of theretainer 30 b and the flat upper side surface 266 of the lower portion46 b of the retainer move into engagement with each other. Material ofthe retainer 30 b tends to flow into the passages 250, 252, 256 and 258formed in the lower and upper sections 46 b and 48 b of the retainer 30b. The portions 32 b and 34 b of the suture 36 b are firmly clampedbetween the side surfaces 266 and 270 on the lower section 46 b andupper section 48 b of the retainer 30 b.

[0142] As the material of the retainer 30 b cools and the applicatorassembly 172 is disengaged from the retainer, there may be a limitedamount of bonding of the material of the retainer 30 b to the portions32 b and 34 b of the suture 36 b. Although the suture 36 b is, to someextent, deformed by force transmitted between the side surfaces 266 and270 on the lower section 46 b and upper section 48 of the retainer 30 b,in the manner illustrated schematically in FIG. 8 for the suture 36, thedeformation of the suture does not weaken the suture.

[0143] It is contemplated that the sections 46 b and 48 b of theretainer 30 b may be made of many different polymeric materials. Thesections 46 b and 48 b of the retainer 30 b may be formed of polymers orcopolymers. It is contemplated that the retainer 30 b may be formed ofbiodegradable or nonbiodegradable materials. In one specific instance,the retainer was made from Poly-L-lactic acid (PLLA) which is aresorbable polymer.

[0144] The suture 36 b may be formed by a single filament or a pluralityof filaments. The suture 36 b may be formed of biodegradable ornonbiodegradable material. It is contemplated that it may be desired toform the suture 36 b of the same material as the retainer 30 b. However,the retainer 30 b and suture 36 b may be formed of different materials.

[0145] Although the foregoing description in the manner in which theretainer 30 b and 36 b are positioned relative to body tissue have beenin conjunction with manual positioning of the applicator assembly 172 bya surgeon, it is contemplated that a robotic mechanism may be utilizedto position the retainer 30 b and/or suture 36 b relative to bodytissue. Thus, a robotic mechanism may be utilize in association with theretainer 30 b and/or suture 36 b in the manner described in theaforementioned U.S. patent application Ser. No. 10/102,413 filed Mar.20, 2002 by Peter M. Bonutti and entitled Methods of Securing BodyTissue. It is contemplated that imaging apparatus may be utilized inassociation with the positioning of the retainer 30 b and/or suture 36 bin the manner disclosed in the aforementioned U.S. patent applicationSer. No. 10/102,413 filed Mar. 20, 2002 by Peter M. Bonutti.

[0146] Embodiment of FIG. 18

[0147] In the embodiment of the invention illustrated in FIG. 18, one ofthe sections of the retainer has a recess which receives the othersection of the retainer. Since the embodiment of the inventionillustrated in FIG. 18 is generally similar to the embodiments of theinvention illustrated in FIGS. 1-8, and 14-17, similar numerals will beutilized to designate similar components, the suffix letter “c” beingassociated with the numerals of FIG. 18 to avoid confusion.

[0148] A retainer 30 c (FIG. 18) includes a lower or base section 46 cand an upper or cover section 48 c. A suture 36 c has portions 32 c and34 c which extend through the retainer 30 c. An intermediate portion 38c of the suture may extend around body tissue in the manner disclosed inFIG. 1. Of course, the suture 36 c may be connected with either hard orsoft body tissue in any desired manner.

[0149] The lower section 46 c of the retainer 30 c has a cylindricalrecess 274 which is sized so as to receive the circular upper section 48c of the retainer 30 c. The lower section 46 c of the retainer haspassages 278 and 280 through which the portion 32 c of the suture 36 cextends. In addition, the lower section 46 c of the retainer 30 c haspassages 282 and 284 through which the portion 34 c of the suture 36 cextends. The recess 274 cooperates with the passages 278,280, 282 and284 to form a central passage through which both portions 32 c and 34 cof the suture extend.

[0150] A pair of projections 288 and 290 extend from the upper section48 c of the retainer 30 c toward the lower section 46 c of the retainer.The projections 288 and 290 have pointed end portions 292 and 294 whichfunction as energy directors and concentrate ultrasonic vibratory energytransmitted from the applicator assembly 172 (FIG. 9) to the uppersection 48 c of the retainer 30 c. The projections 288 and 290 areoffset from the portions of the suture 36 c. One of the projections, forexample, the projection 288, may be offset in a direction into the pageon which FIG. 18 is disposed and the other projection, that is theprojection 290, may be offset in a direction out of the page on whichFIG. 18 is disposed.

[0151] When the suture 36 c and retainer 30 c are to be utilized inassociation with body tissue, the suture 36 c is positioned relative tothe body tissue. The portion 32 c of the suture 36 c is then movedthrough the passages 278 and 280 in the lower section 46 c of theretainer 30 c. The portion 34 c of the suture 36 c is moved through thepassages 282 and 284 of the lower section 46 c of the retainer 30 c.

[0152] The upper section 48 c of the retainer 30 c is then positioned inthe recess 274 with the projections 288 and 290 disposed in linearengagement with a flat upwardly facing side surface 298 on the lowersection 46 c of the retainer 30 c. The pointed ends of the projections292 and 294 do not engage the suture 36 c The retainer 30 c is grippedby the distal end portion (FIG. 12) of the applicator assembly 172. Thisresults in the retainer 30 c being gripped with a constant predeterminedforce transmitted to the retainer 30 c from the biasing spring 180 (FIG.9) through the force transmitting member 176.

[0153] While the surgeon grips the handle 194 of the applicator assembly172 with one hand and grips the portions 32 c and 34 c of the suture 36c with the other hand, the retainer 30 c and leading end portion of theapplicator assembly 172 are moved toward the body tissue. As thisoccurs, the retainer 30 c is slid along the portions 32 c and 34 c ofthe suture 36 c. While the retainer 30 c is slid along the suture 36 c,the retainer is gripped with a constant predetermined force by theapplicator assembly 172.

[0154] When the retainer 30 c is positioned in a desired locationrelative to the suture 36 c and body tissue, energy is transmitted fromthe applicator assembly 172 to the retainer 30 c to interconnect thelower section 46 c and upper section 48 c of the retainer 30 c. Duringthe transmission of energy to the retainer 30 c to interconnect thelower section 46 c and upper section 48 c of the retainer, theapplicator assembly 172 applies a constant predetermined clamping orgripping force to the retainer 30 c. Ultrasonic vibratory energy istransmitted from the end surface 206 on the energy transmission member174 to the upper section 48 c of the retainer 30 c. The pointed endportions 292 and 294 of the projections 288 and 290 engage the flat sidesurface 298 on the lower section 46 c of the retainer. The pointed endportions 292 and 294 of the projection 288 act as energy directors whichconcentrate energy at the pointed end portions of the projections and atthe portion of the surface 298 and engaged by the projections.

[0155] This energy heats the projections 288 and 290 and portions of thelower section 46 c into a transition temperature range. As this occurs,the material of the projections 288 and 290 softens and flows relativeto the suture 36 c and lower and upper sections 46 c and 48 c of theretainer 30 c. The lower and upper sections 46 c and 48 c of theretainer 30 c are clamped together with a constant predetermined forceby the applicator assembly 172 as the material of the projections 288and 290 is heated. The lower and upper sections 46 c and 48 c of theretainer 30 c grip the suture 36 c with a clamping action.

[0156] Material of the retainer 36 c is subsequently allowed to cool andthe trigger 198 on the applicator assembly 172 is actuated to releaseretainer 30 c. As the material of the retainer 30 c cools, the lowersection 46 c and upper section 48 c of the retainer are bonded together.In addition, there is some bonding of the material of the retainer 30 cto the suture 36 c. However, the suture 36 c is primarily securedagainst movement relative the retainer 30 c by clamping the portions 32c and 34 c of the suture 36 c between the lower section 46 c and theupper section 48 c of the retainer 30 c. Although the suture 36 c isslightly deformed, in the manner illustrated schematically in FIG. 8,there is no significant weakening of the suture 36 c.

[0157] It is contemplated that the suture 36 c and retainer 30 c may bepositioned relative to body tissue during minimally invasive surgery.The suture 36 c and retainer 30 c may be positioned relative to the bodytissue by being moved through a cannula. If desired, a robotic mechanismmay be utilized to position the suture 36 c and/or retainer 30 crelative to the body tissue.

[0158] In the embodiment of the invention illustrated in FIG. 18, theupper section 48 c of the retainer 30 c is separate from the lowersection 46 c and is manually moved into the recess 274 after theportions 32 c and 34 c of the suture 36 c have been positioned in thepassages 278, 280, 282 and 284. If desired, the upper section 48 c ofthe retainer 30 c could be connected with the lower section 46 c. Forexample, the upper section 48 c may be positioned in the recess 274. Aninterference fit may be provided between the lower and upper sections 46c and 48 c to hold the upper section in the recess 274. Alternatively,one or more flexible connectors may be used to interconnect the lowerand upper sections. The connector may be a flexible strap. If desired,the connector may be weak sections which are easily broken as the uppersection 48 c moves into the recess 274.

[0159] Embodiment of FIG. 19

[0160] In the embodiments of the invention illustrated in FIGS. 1-8 and14-18, the suture 36 extends through passages in the retainer 30 and isclamped in place. In the embodiment of the invention illustrated in FIG.19, the suture extends through passages in the retainer and is wrappedaround a portion of the retainer, in a manner similar to that previouslydescribed in conjunction with the embodiment of the inventionillustrated in FIG. 13, prior to being clamped in place byinterconnecting of the lower and upper sections of the retainer. Sincethe embodiment of the invention illustrated in FIG. 19 is generallysimilar to the embodiments of the invention illustrated in FIGS. 1-8 and14-18, similar numerals will be utilized to indicate similar components,the suffix letter, “d” being associated with the numerals of FIG. 19 toavoid confusion.

[0161] A retainer 30 d is associated with a suture 36 d. The retainer 30d has a lower section 46 d and an upper section 48 d. The suture 36 dhas a portion 32 d and a portion 34 d which extend through the retainer30 d. An intermediate portion 38 d of the suture 36 d extends betweenthe portions 32 d and 34 d of the suture and may extend around bodytissue in the manner illustrated schematically for the suture 36 in FIG.1.

[0162] The lower section 46 d of the retainer 30 d has a cylindricalcentral projection or post 310. The portion 32 d of the suture 36 dextends through a passage 314 in the lower section 46 d of the retainer30 d and is looped for a plurality of turns around the centralprojection 310. The portion 32 d of the suture 36 d extends from theloops around the central projection 310 through a passage 316 in theupper section 48 d of the retainer 30 d. Similarly, the portion 34 d ofthe suture 36 d extends through a passage 320 in the lower section 46 dand is wrapped for a plurality of loops around the central projection310. The portion 34 d of the suture 36 d extends from the centralprojection 310 through a passage 322 in the upper section 48 d of theretainer 30 d.

[0163] Projections 324 and 326 extend downward (as viewed in FIG. 19)from the upper section 48 d toward a flat upper side surface 330 on thelower section 46 d. The projections 324 and 326 are offset from thecentral projection 310 and from the openings 314 and 320 in the lowersection 46 d. Although only two projections 324 and 326 are illustratedin FIG. 19, a greater number of projections may be provided if desired.

[0164] The suture 36 d is positioned relative to body tissue in the samemanner as is illustrated schematically for the suture 36 in FIG. 1. Thismay be done during arthroscopic or laproscopic surgery. To minimize thesize of an incision in a patient's body, the suture may be moved througha cannula into the patient's body and positioned relative to hard and/orsoft body tissue. The portions 32 d and 34 d of the suture may extendfrom the cannula and be readily accessible to a surgeon.

[0165] The portion 32 d of the suture is inserted through the passage314 and wrapped for a plurality of turns around the central projection310. The portion 34 d of the suture is inserted through the passage 320and is also wrapped for a plurality of turns around the centralprojection 310. The portion 34 d of the suture is inserted through thepassage 322 in the upper section 48 d of the retainer 30 d. The portion32 d of the suture 36 d is inserted through the passage 316 in the uppersection 48 d of the retainer 30 d.

[0166] The upper section 48 d of the retainer 30 d is moved along theportions 32 d and 34 d of the suture until the projections 324 and 326from the upper section 48 d of the retainer 30 d engage the flat upperside surface 330 of the lower section 46 d of the retainer. As thisoccurs, the central projection 310 enters a cylindrical opening 334 inthe upper section 48 d of the retainer 30 d. As the central projection310 is telescopically inserted into the opening 334, the turns of theportions 32 d and 34 d of the suture 36 d are disposed around thecentral projection move downward (as viewed in FIG. 19) toward the flatsurface 330 on the lower section 46 d of the retainer 30 d.

[0167] The projections 324 and 326 are offset from the portions 32 d and34 d of the suture 36 d. The pointed projections 324 and 326 engage theflat surface 330 on the lower section 46 d of the retainer 30 d. Theprojections 324 and 326 are spaced from the suture 36 d and prevent thesuture from being gripped between the lower section 46 d and uppersection 48 d of the retainer 30 d.

[0168] The retainer 30 d is then gripped by the distal end portion ofthe applicator assembly 172 (FIG. 12). The applicator assembly 172 gripsthe retainer 30 d with a constant force which is determined by thespring 180 (FIG. 9).

[0169] While the retainer 30 d is gripped by the applicator assembly172, the retainer is slid along the portions 32 d and 34 d (FIG. 19) ofthe suture 36 d toward the body tissue. As this occurs, the distal endportion of the applicator assembly 172 and the retainer 30 d may bemoved through a cannula or through an open incision. Regardless ofwhether or not the retainer 30 d is moved through a cannula, theretainer is positioned in engagement with body tissue, similar to thebody tissue of 40 of FIG. 1, while the retainer is gripped with thepredetermined constant force by the applicator assembly 172.

[0170] Once the retainer 30 d has been positioned relative to the bodytissue, the portions 32 d and 34 d of the suture 36 d are tensioned witha predetermined force. While the suture 36 d is tensioned with apredetermined force, ultrasonic vibratory energy is transmitted from asource of energy, corresponding to the energy source 212 of FIG. 9, tothe retainer 30 d. The energy is transmitted to the retainer 30 dthrough the energy transmission member 174. The energy transmitted tothe retainer 30 d heats the projections 324 and 326 and the material ofthe lower section 46 d of the retainer engaged by the projections.

[0171] The projections 324 and 326 have a pointed configuration andfunction as energy directors which concentrate the energy transmittedfrom the source 212. This results in heating of the projections 324 and326 and a portion of the lower section 46 d of the retainer 30 d engagedby the projections to temperatures in the transition temperature rangeof the material of the retainer 30 d. As this occurs, the lower andupper sections 46 d and 48 d of the retainer 30 d are moved togetherunder the influence of the constant predetermined force applied againstthe retainer by the applicator assembly 172. This results in the loopsof the suture disposed around the central projection 310 being firmlygripped between the flat upper side surface 330 of the lower section 46d of the retainer and a flat lower side surface 338 on the upper section48 d of the retainer.

[0172] The trigger 198 on the applicator assembly 172 is then manuallyactuated to release the retainer 30 d. As this occurs, the retainer 30 dcools. A secure bond is formed between the lower section 46 d and uppersection 48 d of the retainer at the locations where the projections 324and 326 from the upper section 48 d of the retainer engage the lowersection 46 d of the retainer. A robotic mechanism may be utilized toposition the suture 36 d and/or retainer 30 d relative to body tissue.

[0173] It is contemplated that the retainer 30 d and suture 36 d may beformed of either biodegradable or nonbiodegradable material. Theretainer 30 d and suture 36 d may be formed of the same materials or ofdifferent materials. For example, the suture 36 d could be formed of abiodegradable material while the retainer 30 d is formed of anonbiodegradable material. Alternatively, both the suture 36 d andretainer 30 d may be formed of a biodegradable material.

[0174] Embodiment of FIGS. 20 and 21

[0175] In the embodiment of the invention illustrated in FIGS. 20 and21, a suture is clamped between and held by sections of a retainer.Since the embodiment of the invention illustrated in FIGS. 20 and 21 isgenerally similar to the embodiments of the invention illustrated inFIGS. 1-8 and 13-19, similar numerals will be utilized to designatesimilar components, the suffix letter “e” being associated with thenumerals of FIGS. 20 and 21 to avoid confusion.

[0176] A retainer 30 e includes lower and upper sections 46 e and 48 e.A suture 36 e (FIG. 20) has portions 32 e and 34 e which extend throughthe retainer 30 e. The portions 32 e and 34 e of the suture 36 e areinterconnected by an intermediate portion 38 e of the suture. A loop 230e is formed in the portion 32 e of the suture 36 e and extends aroundpart of the lower section 46 e of the retainer 30 e. Similarly, a loop232 e is formed in the portion 34 e of the suture 36 e and extendsaround part of the lower section 46 e of the retainer 30 e.

[0177] The lower section 46 e of the retainer 30 e includes a circularbottom wall 344 (FIG. 21) having a flat upwardly facing side surface346. A cylindrical side wall 350 extends upward from the bottom wall344. The side wall 350 cooperates with the bottom wall 344 to form acylindrical recess 274 e (FIG. 21). The upper section 48 e has acircular body 64 e which has a diameter which is only slightly greaterthan an inside diameter cylindrical side wall 350 e. This results in aninterference fit between the upper section 48 e and lower section 46 eof the retainer 30 e when the upper section 64 e is inserted into thecylindrical recess 274 e.

[0178] While the upper section 48 e is held in the cylindrical recess274 e in the lower section 46 e of the retainer 30 e, the portions 32 eand 34 e of the suture 36 e are inserted through the retainer 30 e inopposite directions. Thus, the suture 32 e is inserted through a passage354 (FIG. 20) in the side wall 350 of the lower section 46 e of theretainer 30 e. The portion 32 e of the suture is inserted through therecess 274 e (FIG. 21) to a second passage 356 formed in the side wall350 of the lower section 46 e of the retainer.

[0179] The suture is wrapped around the outside of the side wall 350 andinserted through the passage 354 for a second time. The end portion 32 eof the suture 36 e is then moved through the passage 356 e in the sidewall for a second time. This forms the loop 230 e around a portion ofthe side wall 350 in the manner illustrated schematically in FIG. 20.

[0180] Similarly, the portion 34 e of the suture 36 e is insertedthrough a passage 360 formed in the side wall 350 (FIGS. 20 and 21) intothe cylindrical recess 274 e. The portion 34 e of the suture is insertedthrough the cylindrical recess 274 e and through another passage 362formed in the side wall 350 of the lower section 46 e of the retainer 30e. The portion 34 e of the suture 36 e is wrapped around the outside ofthe side wall 350 (FIG. 20) and inserted for a second time through thepassage 360. The portion 34 e of the suture is inserted through therecess 274 e and the opening 362 e to form the loop 232 e around theportion of the lower section 46 e of the retainer 30 e.

[0181] The upper section 48 e of the retainer 30 e has a plurality ofpointed projections 366 and 368 (FIG. 20). When the upper section 48 eof the retainer 30 e is disposed in the recess 274 e, the projections366 and 368 are enclosed by the loops 230 e and 232 e. The projections366 and 368 have pointed end portions with a configuration similar tothe configuration of the pointed end portions 124 and 126 on theprojections 66 and 68 of FIGS. 3-7. The end portions of the projections366 and 368 engage the side surface 346 on the bottom wall 344 when theupper section 48 e is disposed in the cylindrical recess 274 e. There isline contact between the end portions of the projections 366 and 368 andthe surface 346 on the bottom wall 344. The pointed end portions of theprojections 366 and 368 are spaced from the suture 36 e.

[0182] The upper section 48 e of the retainer 30 e has a secondplurality of projections 374 and 376 (FIGS. 20 and 21). The projections374 and 376 have the same configurations as the projections 366 and 368.The projections 374 and 376 have pointed end portions 378 and 380 (FIG.21). The pointed end portions 378 and 380 on the projections 374 and 376engage the flat side surface 346 on the bottom wall 344 when the uppersection 48 e of the retainer 30 e is disposed in the cylindrical recess274 e. The projections 374 and 376 are disposed within the loop 332 eformed in the portion 34 e of the suture 36 e. The pointed end portionsof the projections 374 and 376 are spaced from the suture 36 e.

[0183] When the retainer 30 e and suture 36 e are to be used to securebody tissue during a surgical procedure, the intermediate portion 38 eof the suture is positioned relative to the body tissue. At this time,the upper section 48 e of the retainer 30 e is disposed in thecylindrical recess 274 e in the lower section 46 e and the projections366, 368, 374 and 376 are disposed in engagement with the side surface246 of the bottom wall 344 of the retainer. The upper section 48 e ofthe retainer 30 e is held in the recess 274 e by an interference fitbetween a cylindrical inner side surface of the side wall 350 and anouter side surface of the body 64 e of the upper section.

[0184] After the intermediate portion 38 e of the suture 36 e has beenpositioned relative to body tissue, the portion 32 e of the suture ismoved downward (as viewed in FIG. 20) through the passage 354 and alongthe projections 366 and 368. The portion 32 e of the suture 36 e is thenmoved through the passage 356 and wrapped around the outside of theretainer 30 e. The portion 32 e of the suture is again moved downward(as viewed in FIG. 20) through the passages 354 and 356 to form the loop230 e.

[0185] The portion 34 e of the suture 36 e is inserted upward (as viewedin FIG. 20) through the passage 360 and along the projections 374 and376. The portion 34 e of the suture is then moved through the passage362 and wrapped around the outside of the bottom section 46 e of theretainer 30 e. The portion 34 e of the suture is again upward (as viewedin FIG. 20) through the passages 360 and 362 to form the loop 232 e.When this has been done, the portions 32 e and 34 e of the suture extendin opposite directions from the retainer 30 e and the intermediateportion 38 e of the suture extends in opposite directions from theretainer.

[0186] The retainer is then gripped with the distal end portion (FIG.12) of the applicator assembly 172. The applicator assembly 172 gripsthe retainer 30 e with a constant predetermined force.

[0187] While the retainer 30 e is gripped with a constant predeterminedforce by the applicator assembly 172, a surgeon manually holds thehandle 194 of the applicator assembly 172 (FIGS. 9 and 10) with one handand tensions the portions 32 e and 34 e of the suture 36 e with theother hand. While tensioning the suture 36 e, the surgeon slides theretainer 30 e along the suture toward the body tissue. As it waspreviously mentioned, this may involve moving of the retainer 30 e andthe distal end portion of the applicator assembly 172 through a cannulato position the retainer relative to the body tissue. A roboticmechanism may be utilized to position the suture 36 e and/or retainer 30e relative to body tissue.

[0188] When the retainer has been positioned at a desired locationrelative to the body tissue in the manner similar to the schematicillustration of FIG. 1, energy is transmitted from the energy source 212through the energy transmission member 174 to the retainer 30 e.Although the energy is ultrasonic vibratory energy, it is contemplatedthat it could be a different type of energy if desired. For example,radio frequency, fight, or thermal energy could be transmitted to theretainer 30 e.

[0189] The ultrasonic vibratory energy transmitted to the retainer 30 eis concentrated by the projections 366, 368, 374 and 376 which functionas energy directors. The concentrated energy heats the projections 366,368, 374 and 376 and the portion of the bottom wall 344 of the lowersection 46 e of the retainer 30 e engaged by the projections, to atemperature in a transition temperature range for the material of theretainer. The retainer may be formed of a polymeric material which is apolymer or copolymer. The material of the retainer 30 e may bebiodegradable or nonbiodegradable.

[0190] As the projections 374 and 376 are heated and softened, the uppersection 48 e of the retainer is pressed toward the bottom wall 344 ofthe lower section 46 e of the retainer 30 e by the applicator assembly172. The force applied against the retainer 30 e is effective to causethe softened material of the projections 366, 368, 374 and 376 to flowin the recess 274 e. As this occurs, the upper section 48 e of theretainer 30 e moves toward the bottom wall 344 of the lower section 46 eof the retainer. This results in the portions 32 e and 34 e of thesuture 36 e being securely clamped between the lower section 46 e andupper section 48 e of the retainer 30 e.

[0191] When the material of the projections 374 and 376 has cooled, thelower section 46 e and upper section 48 e of the retainer are securelybonded together to maintain a secure grip on the suture 36 e. Althoughthere may be some bonding of the material of the projections 366, 368,374 and 376 to the suture 36 e, there is no significant weakening of thesuture.

[0192] Embodiment of FIG. 22

[0193] The retainer of the embodiment of the invention illustrated inFIG. 22 is generally similar to the retainers of FIGS. 1-8 and 13-21.Numerals similar to the numerals utilized in conjunction with FIGS. 1-8and 13-21 will be utilized to designate similar components, the suffixletter “f” being associated with the numerals of FIG. 22 to avoidconfusion.

[0194] A retainer 30 f has a lower section 46 f and an upper section 48f. A suture 36 f has portions 32 f and 34 f which extend through theretainer 30 f. An intermediate portion 38 f of the suture 36 f extendsbetween the portions 32 f and 34 f and may extend around body tissue inthe manner illustrated schematically in FIG. 1 for the suture 36.

[0195] The portion 32 f of the suture 36 f extends through a passage 384in the lower section 46 f of the retainer 30 f. The portion 32 f of thesuture extends through a passage 386 formed in the upper section 48 f ofthe retainer 30 f. The portion 32 f of the suture is wrapped around aportion 390 of the upper section 48 f of the retainer 30 f. The portion32 f of the suture is again inserted through the passage 386 to form aloop 230 f around the portion 390 of the upper section 48 f of theretainer 30 f.

[0196] Similarly, the portion 34 f of the suture 36 f extends through apassage 394 in the lower section 46 f of the retainer 30 f. The portion34 f of the suture 36 f extends through a passage 396 in the upperportion 48 f of the retainer 30 f. The portion 34 f of the suture 36 fis wrapped around a portion 398 of the upper section 48 f of theretainer 30 f to form a loop 232 f.

[0197] Projection 400 extends from the upper section 48 f of theretainer 30 f. The projection 400 is engagable with a flat upper sidesurface 402 of the lower section 46 f of the retainer 30 f. Theprojection 400 has a pointed end portion which functions as an energydirector which concentrates energy.

[0198] When the retainer 30 f and suture 36 f are utilized to securebody tissue, in a manner similar to that manner illustratedschematically in FIG. 1, the suture 36 f is positioned relative to thebody tissue with the intermediate portion 38 f of the suture inengagement with the body tissue. The portion 32 f of the suture isinserted through the passages 384 and 386 in the lower and uppersections 46 f and 48 f of the retainer 30 f. The portion 32 f of thesuture is then wrapped around the portion 390 of the upper section 48 fof the retainer 30 f and again inserted through the passage 386.

[0199] The portion 34 f of the suture 36 f is inserted through thepassage 394 in the lower section 46 f of the retainer 30 f and throughthe passage 396 in the upper section 48 f of the retainer. The portion34 f of the suture 36 f is wrapped around the portion 398 of the uppersection 48 f of the retainer 30 f and again inserted through the passage396.

[0200] The retainer 40 f is then gripped by the distal end portion (FIG.12) of the applicator assembly 172 (FIGS. 9 and 10). This results in theprojection 400 being pressed against the upper side surface 402 of thelower section 46 f of the retainer 30 f with a predetermined constantforce. While the retainer 30 f is gripped by the distal end portion ofthe applicator assembly 172, a surgeon grips the portions 32 f and 34 fof the suture 36 f with one hand and grips the handle 194 of theapplicator assembly 172 with the other hand. While tensioning theportions 32 f and 34 f, the surgeon slides the retainer 30 f along thesuture 36 f toward the body tissue. As it was previously mentioned, thismay involve moving both the retainer 30 f and the distal end portion ofthe applicator assembly 172 through a cannula.

[0201] A robotic mechanism may be utilized to position the suture 36 f,and/or retainer 30 f relative to body tissue. Alternatively, the suture36 f and/or retainer 30 f may be manually positioned relative to thebody tissue.

[0202] Once the retainer 30 f has been positioned relative to bodytissue, energy is transmitted from a source 212 (FIG. 9) through theenergy transmission member 174 to the retainer 30 f. The pointedprojection 400 functions as energy director and is effective toconcentrate the ultrasonic vibratory energy in the projection 400 and inthe portion of the lower section 48 f of the retainer 30 f engaged bythe projection 400. The energy transmitted to the retainer 30 f iseffective to heat the projection 400 and the portion of the lowersection 46 f of the retainer engaged by the projection, into thetransition temperature range for the material of the retainer 30 f.

[0203] Once the material of the retainer 30 f has been heat softened,the material can flow under the influence of the constant predeterminedforce with which the applicator assembly 172 grips the retainer 30 f.This results in deformation of the projection 400 and movement of thelower and upper sections 46 f and 48 f of the retainer 30 f together toclamp the portions 32 f and 34 f of the suture 36 f between the flatupper side surface of the lower section 46 f and flat lower side surface404 of the upper section 48 f of the retainer.

[0204] When the material of the retainer 30 f has cooled, the trigger198 on the applicator assembly 172 is actuated and the retainer isreleased. The lower and upper sections 46 f and 48 f of the retainer 30f are bonded together and maintain the clamping action against theportions 32 f and 34 f of the suture 36 f to prevent relative movementbetween the retainer 30 f and the suture 36.

[0205] Although only a single projection 400 has been illustratedschematically in FIG. 22, it should be understood that a plurality ofprojections may be provided. This would result in bonds being formedbetween the lower and upper section 46 f and 48 f of the retainer 30 fat each of a plurality of projections.

[0206] Embodiment of FIG. 23

[0207] The embodiment of the invention illustrated in FIG. 23 isgenerally similar to the embodiments of FIGS. 1-8 and 13-22. Therefore,similar numerals will be utilized to designate similar components, thesuffix letter “g” being associated with the numerals of FIG. 23 to avoidconfusion.

[0208] A retainer 30 g includes a lower section 46 g and an uppersection 48 g. The retainer 30 g may be formed of a polymeric materialwhich is either a polymer or copolymer. The retainer 30 g may bebiodegradable or nonbiodegradable.

[0209] A suture 36 g has a portion 32 g which extends through theretainer 30 g and a portion 34 g which also extends through theretainer. The suture 36 g may be formed of a plurality of filaments or asingle filament. The suture 36 g is formed of a polymeric material whichis either a polymer or a copolymer. The suture 36 g may be formed of amaterial which biodegradable or of a material which is nonbiodegradable.The retainer 30 g and suture 36 g may be formed of the same material orof different materials.

[0210] When the retainer 30 g and suture 36 g are to be used to securebody tissue, in a manner similar to the manner illustrated schematicallyin FIG. 1, an intermediate portion 38 g of the suture is positionedaround body tissue. The portions 32 g and 34 g of the suture 36 g arethen positioned relative to the lower and upper sections 46 g and 48 gof the retainer 30 g.

[0211] When this is to be done, a portion 32 g of the suture 36 g isinserted through a passage 410 in the lower section 46 g of the retainer30 g. The portion 32 g of the suture 36 g is wrapped around a portion412 of the lower section 46 g of the retainer 30 g. The portion 329 ofthe suture is then inserted through the passage 410 for a second timeforms a loop 230 g around the portion 412 of the lower section 46 g ofthe retainer 30 g. The portion 32 g of the suture 36 g is then insertedthrough a passage 414 in the upper section 48 g of the retainer 30 g.

[0212] Similarly, the portion 34 g of the suture 36 g is insertedthrough a passage 420 in the lower section 46 g of the retainer 30 g.The portion 34 g of the suture 36 g is then wrapped around the portion422 of the lower section 46 g to form a loop 232 g. The portion 34 g ofthe suture 36 g is then inserted through the passage 420 for a secondtime. The portion 34 g of the suture 36 g is then inserted through apassage 426 in the upper section 48 g of the retainer 30 g.

[0213] The sections 46 g and 48 g of the retainer 30 g are then movedtogether. As this occurs, a projection 400 g from the upper section 48 gmoves into engagement with a flat upper side surface 402 g on the lowersection 46 g of the retainer 30 g. The retainer 30 g is then grippedwith the distal end portion (FIG. 12) of the applicator assembly 172.The applicator assembly 172 grips the retainer 30 g with a constantpredetermined force.

[0214] When the retainer 30 g and suture 36 g are to be utilized tosecure body tissue, in the manner similar to that illustratedschematically in FIG. 1, the suture 36 g is positioned with theintermediate portion 38 g of the suture extending around the bodytissue. The portions 32 g and 34 g of the suture 36 g are positionedrelative to the upper and lower sections 46 g and 48 g in the mannerpreviously described and illustrated schematically in FIG. 23.

[0215] While the surgeon grips the handle 194 of the applicator assembly172 with one hand and grips the portions 32 g and 34 g of the suture 36g with the other hand, the retainer 30 g is slid along the suture towardthe body tissue. As the retainer 30 g is slid along the suture 36 gtoward the body tissue, the retainer is gripped with a constantpredetermined force by the applicator assembly 172. When the retainer 30g has been moved to a desired position relative to the body tissue,energy is transmitted from the source 212 to the energy transmissionmember 174. Although many different types of energy may be utilized, theenergy transmitted to the retainer 30 g from the energy transmissionmember 174 is ultrasonic vibratory energy.

[0216] The projection 40 g has a pointed configuration and functions asan energy director which concentrates the ultrasonic vibratory energytransmitted from the energy transmission member 174 to the retainer 30g. The projection 400 g and the material of the lower section 46 gengaged by the projection are heated into their transition temperatureranges. Heating of the materials of the projection 400 g into itstransition temperature range enables the material to flow under theinfluence of the constant predetermined force applied against theretainer 30 g by the applicator assembly 172. This results in the suture36 g being firmly clamped between the flat upper side surface 402 g ofthe lower section 46 g and a flat lower side surface 404 g of the uppersection 48 g of the retainer 30 g. The material of the projection 400 gbonds to the material of the lower section 46 g of the retainer 30 g.This results in the clamping force applied against the suture 36 g bythe lower and upper sections 46 g and 48 g of the retainer 30 g beingmaintained.

[0217] Although only a single projection 400 g has been illustratedschematically in FIG. 23, it is contemplated that a plurality ofprojections may be provided. Each of the projections from the uppersection 48 g of the retainer 30 g would engage the upper side surface402 g of the lower section 46 g of the retainer. This would result in aplurality of bonds being formed between the lower section 46 g and uppersection 48 g of the retainer.

[0218] Embodiment of FIG. 24

[0219] It is contemplated that the applicator assembly 172 (FIGS. 9-12)may be utilized to position any one of the retainers of FIGS. 1-8 and13-23 relative to body tissue 40. The applicator assembly 172 isoperable to bond upper and lower sections of any one of the retainersdisclosed herein together to maintain a secure grip on portions 32 and34 of the sutures 36. It should be understood that the applicatorassembly 172 may be used with retainers other than the retainersdisclosed herein.

[0220] In the embodiment of FIG. 24, the applicator assembly 172,retainer 30 and suture 36 have been illustrated in associated with acannula 450. It should be understood that the applicator assembly 172,suture 36 and any one of the retainers 30 disclosed herein may beutilized without the cannula 450. However, by using the cannula 450, itis believed that minimally invasive surgery will be facilitated. Ofcourse, the suture 36, retainer 30, and applicator assembly 172 may beutilized during surgical procedures which are not minimally invasivesurgical procedures.

[0221] When the cannula 450 is to be utilized during a surgicalprocedure, the cannula is moved through body tissue 452 to a position inwhich a distal end portion 454 of the cannula 450 is adjacent to thebody tissue 40 to be engaged by the suture 36. The proximal end portion456 of the cannula 450 extends from the body tissue 452 in the mannerillustrated schematically in FIG. 24. Once the cannula 450 has beenpositioned relative to the body tissue 40, the suture 36 is movedthrough the cannula and positioned relative to the body tissue. Theportions 32 and/or 34 of the suture may be moved through the cannula 450to position the suture relative to the body tissue. The portions 32and/or 34 of the suture are then pulled from the cannula 450 with theintermediate portion 38 of the suture engaging the body tissue 40.

[0222] The portions 32 and 34 of the suture 36 are then inserted throughone or more passages in the retainer 30. Once the portions 32 and 34 ofthe suture have been inserted through the retainer 30, the retainer isgripped by the applicator assembly 172 in the manner illustratedschematically in FIG. 24. When the retainer 30 is gripped by theapplicator assembly 172, a constant predetermined force is appliedagainst the retainer 30 by the applicator assembly 172.

[0223] A surgeon may then manually grasp the portions 32 and 34 of thesuture and tension the suture. At the same time, the surgeon manuallygrasps the handle 194 (FIG. 10) on the applicator assembly 172 and movesthe applicator assembly downward (as viewed in FIG. 24) toward thecannula 450. As this occurs, the retainer 30 slides along the portions32 and 34 of the suture and approaches the proximal end portion 456 ofthe cannula 450.

[0224] Continued movement of the applicator assembly 172 toward the bodytissue 40 slides the retainer 30 along the portions 32 and 34 of thesuture 36 as the leading end portion of the applicator assembly andretainer enter the cannula. The downward (as viewed in FIG. 24) movementof the applicator assembly 172 and retainer 30 is continued whiletension is maintained in the portions 32 and 34 of the suture 36. Thisresults in the retainer 30 sliding along the portions 32 and 34 of thesuture 36 as the retainer 30 is moved through the cannula 450 by theapplicator assembly 172.

[0225] The retainer 30 and leading end portion of the applicatorassembly 172 may be moved through the distal end portion 454 of thecannula 450 and positioned in engagement with the body tissue 40.Alternatively, the distal end portion 454 of the cannula may be placedin engagement with the body tissue and the retainer moved intoengagement with a surface area of the body tissue 40 which is surroundedby the distal end portion 454 of the cannula 450.

[0226] Once the retainer 30 has been positioned at a desired locationrelative to the body tissue 40, the portions 32 and 34 of the suture 36are tensioned with a desired force. The manner in which the portions 32and 34 of the suture 36 are tensioned with a predetermined force may bethe same as is disclosed in U.S. Pat. No. 6,159,234 or in U.S. patentapplication Ser. No. 09/556,458 filed May 3, 2000 by Peter M. Bonuttiand entitled Method And Apparatus For Securing Tissue. Of course, apredetermined tension may be established in the portions 32 and 34 ofthe suture 36 in a different manner if desired.

[0227] While the predetermined tension is maintained in the portions 32and 34 of the suture, the switch 214 (FIG. 9) is closed and ultrasonicvibratory energy is conducted through the energy transmission member 174to the retainer 30. The ultrasonic vibratory energy is effective to heatpointed end portions of one or more projections on the retainer 30. Thisresults in a bonding between upper and lower sections of the retainer inthe manner previously described in conjunction with the retainers ofFIGS. 1-8 and 13-23.

[0228] The switch 214 is then released and the flow of ultrasonicvibratory energy to the retainer 30 is interrupted. When this occurs,the retainer cools and an ultrasonic weld is formed between the sectionsof the retainer. The trigger 198 on the applicator assembly 172 is thenactuated to move the force transmitting member 176 axially downward (asviewed in FIG. 24) to release the retainer 30. When the applicatorassembly 172 has been disengaged from the retainer 30, it is removedfrom the cannula 450. The end portions 32 and 34 of the suture 36 maythen be cut to a desired length or connected with other body tissue.

[0229] Although in the specific embodiment of the invention illustratedin FIG. 24 the suture 36 and retainer 30 are utilized in associationwith soft body tissue, it is contemplated that the suture 36 andretainer 30 may be used in association with hard body tissue or withboth hard and soft body tissue. It is contemplated that the suture 36may be connected with body tissue in known ways other than the specificway illustrated schematically in FIG. 24. The looping of the suture 36around the body tissue 40 in FIG. 24 is merely a representation of anyone of the many known ways of connecting a suture with body tissue.

[0230] Rather than being manually actuated, the applicator assembly 172may form a portion a robotic mechanism. The robotic mechanism may beoperated to tension the suture 36 with a desired tension, slide theretainer 30 along the suture, and transmit energy to the retainer in themanner previously described in conjunction with the applicator assembly172. The robotic mechanism may be constructed and used in associationwith imaging devices in the same manner disclosed in U.S. patentapplication Ser. No. 10/102,413 filed Mar. 20, 2002 by Peter M. Bonuttiand entitled Methods of Securing Body Tissue. It is contemplated thatthe cannula 450 may have any one of many different known constructions,including the constructions disclosed in U.S. Pat. Nos. 6,338,730 and6,358,266.

[0231] Embodiment of FIG. 25

[0232] In the embodiment of the invention illustrated in FIG. 12, theapplicator assembly 172 is provided with a flange 204 which engages agroove 142 in a retainer 30. In addition, the distal end portion of theapplicator assembly 172 of FIGS. 9-12 is exposed so that a retainergripped between the flange 204 and the end surface 206 on thetransmission member 174 is exposed to body fluids. In the embodiment ofthe invention illustrated in FIG. 25, the distal end portion of theapplicator assembly is provided with an end plate rather than a flangeand a shield cooperates with the end plate to enclose the retainer.Since the embodiment of the invention illustrated in FIG. 25 isgenerally similar to the embodiment of the invention illustrated inFIGS. 9-12, similar numerals will be utilized to designate similarcomponents, the suffix letter “h” being associated with the numerals ofFIG. 25 to avoid confusion.

[0233] An applicator assembly 172 h (FIG. 25) includes a tubular forcetransmitting member 176 h. The tubular force transmitting member 176 hextends around and is coaxial with an energy transmission member 174 h.The energy transmission member 174 h has a circular end surface 206 hwhich is engagable with a retainer 30 in a manner similar to thatillustrated in FIG. 24.

[0234] The metal end plate 464 is connected with the force transmittingmember 176 h. The metal end plate 464 replaces the flange 204 of theembodiment of the applicator assembly 172 illustrated in FIGS. 9-12 andis effective to apply force against the lower section of a retainer 30in the manner previously described in conjunction with the retainers ofFIGS. 1-8 and 13-23. The end plate 464 eliminates the necessity for thegroove 142 in the lower section 46 of the retainer 30 (FIGS. 3-7). Inaddition, the end plate 464 provides for a relatively even distributionof force against the retainer 30 as it is clamped between the forcetransmitting member 176 and energy transmission member 174 with aconstant predetermined force in the manner illustrated schematically inFIG. 24. The applicator assembly 172 h has the same general constructionand mode of operation as the applicator assembly 172 of FIGS. 9-12.

[0235] In accordance with a feature of the embodiment of the inventionillustrated in FIG. 25, a flexible shield 468 is connected with tubularforce transmitting member 176. The shield 468 cooperates with the endplate 464 to enclose a retainer 30 gripped between the energytransmission member 174 and the end plate. The proximal end portion 470of the shield 468 is fixedly connected to the tubular force transmittingmember 176. The distal end portion 472 of the shield 468 is free to moverelative to the end plate 464 and force transmitting member 176. Thisprovides access to the space between the end plate 464 and the endsurface 206 on the energy transmission member 174 h to position theretainer 30 between the end plate 464 and the end surface 206 h on theenergy transmission member 174 h.

[0236] The shield cooperates with the force transmitting member 176 h toenclose the retainer 30. This minimizes exposure of the retainer 30 tobody tissue and/or body fluids. However, the flexible material of theshield 468 enables the portions 32 and 34 of the suture 36 to extendfrom the distal end portion of the applicator assembly 172.

[0237] Conclusion

[0238] In view of the foregoing description, it is apparent that thepresent invention relates to a new and improved apparatus and method foruse in securing a suture 36. The suture 36 is positioned relative tosections 46 and 48 of an improved retainer 30. The sections 46 and 48 ofthe retainer 30 are interconnected when the retainer has been positionedrelative to a patient's body tissue 40. The sections 46 and 48 of theretainer 30 may be bonded together by the application of energy to theretainer by an improved applicator assembly 172.

[0239] The improved retainer 30 may have one or more projections 66 and68 which engage one or more recesses 58 and 60 to position the sections46 and 48 of the retainer relative to each other. An interference fitmay be provided between one or more projections 66 and 68 and one ormore recesses 58 and 60 to hold the sections 46 and 48 of the retainer30 in a desired spatial relationship. The projections 66 and 68 may havesurfaces 88 and 90 which at least partially define one or more passages52 and 54 and guide movement of one or more portions 32 and 34 of thesuture 36 relative 30 to the retainer. In addition, surfaces on theprojections may function to position the suture relative to theretainer.

[0240] The improved applicator assembly 172 may be used to apply energyto the retainer 30. Energy applied to the retainer 30 may effect bondingof end portions 124 and 126 of the projections 66 and 68 to bottomportions 118 and 120 of recesses 68 and 60 in the retainer 30. The endportions 124 and 126 of the projections 58 and 60 may function as energydirectors which concentrate energy. If desired, one or more loops 230and 232 may be formed in the suture 36 around one or more of theprojections 66 and 68.

[0241] The applicator assembly may grip the retainer 30 with apredetermined force. While the applicator assembly 172 grips theretainer 30, the applicator assembly may be utilized to slide theretainer along the suture 36 to position the retainer relative to bodytissue. While the applicator assembly 172 is gripping the retainer 30,the applicator assembly may apply energy to the retainer to effectbonding of sections 46 and 48 of the retainer together. The applicatorassembly 172 may be used to move the retainer 30 into a cannula 450 toengage tissue in a patient's body.

[0242] The present invention includes a plurality of different featureswhich may be utilized in combination with each other or separately. Thevarious features of the invention may be used in combination withfeatures of the prior art. For example, the improved retainer 30 may beused with the improved applicator assembly 172 or with a prior artapplicator assembly. As another example, the improved applicatorassembly 172 may be used with the improved retainer 30 or a prior artretainer. As still another example, the retainer 30 may be moved througha cannula 450 to a desired position relative to body tissue or may bepositioned relative to the body tissue without being moved through acannula.

Having described the invention, the following is claimed:
 1. A method ofsecuring a suture, said method comprising the steps of moving a firstportion of the suture through a first passage which extends betweenfirst and second sections of a retainer, moving a second portion of thesuture through a second passage which extends between the first andsecond sections of the retainer, and interconnecting the first andsecond sections of the retainer with the first and second portions ofthe suture at least partially disposed in the first and second passages,said step of interconnecting the first and second sections of theretainer includes decreasing size of the first and second passages andapplying energy to at least one of the first and second sections of theretainer.
 2. A method as set forth in claim 1 further including the stepof providing an interference fit between portions of the first andsecond sections of the retainer to maintain the first and secondsections of the retainer in a desired spatial relationship during movingof the first portion of the suture through the first passage and duringmoving of the second portion of the suture through the second passage.3. A method as set forth in claim 1 wherein said step of applying energyto at least one of the first and second sections of the retainerincludes engaging a recess formed in the first section of the retainerwith a first member, engaging the second section of the retainer with asecond member, and transmitting energy to the retainer through at leastone of the first and second members.
 4. A method as set forth in claim 1further including the steps of gripping the retainer with an applicatorassembly, and sliding the retainer along the first and second portionsof the suture while gripping the retainer with the applicator assembly.5. A method as set forth in clam 4 wherein said step of applying energyto at least one of the first and second sections of the retainerincludes transmitting energy from the applicator assembly to theretainer.
 6. A method as set forth in claim 4 wherein said step ofgripping the retainer includes gripping the retainer with apredetermined force and maintaining the force with which the retainer isgripped at least substantially constant during performance of said stepof sliding the retainer along the first and second portions of thesuture.
 7. A method as set forth in claim 6 wherein said step ofapplying energy to at least one of the first and second sections of theretainer includes transmitting energy from the applicator assembly whilegripping the retainer with the predetermined force.
 8. A method as setforth in claim 1 further including the step of engaging first and secondrecesses in the first section of the retainer with first and secondprojections extending from the second section of the retainer toposition the second section of the retainer relative to the firstsection of the retainer during performance of said step of moving afirst portion of a suture through a first passage and during performanceof said step of moving a second portion of a suture through a secondpassage.
 9. A method as set forth in claim 8 further including the stepsof forming a loop in the first portion of the suture around the firstprojection by moving the first portion of the suture through the firstpassage for a second time, and forming a loop in the second portion ofthe suture around the second projection by moving the second portion ofthe suture through the second passage for a second time.
 10. A method asset forth in claim 8 further including the steps of moving portions ofthe first and second projections into the first and second recessesduring performance of said step of interconnecting the first and secondsections of the retainer.
 11. A method as set forth in claim 1 whereinsaid step of moving a first portion of a suture through a first passageincludes moving the first portion of the suture in a first directionrelative to the first and second sections of the retainer, said step ofmoving a second portion of a suture through a second passage includesmoving the second portion of the suture in a second direction relativeto the first and second sections of the retainer.
 12. A method as setforth in claim 1 wherein a plurality of projections are disposed betweenthe first and second sections of the retainer and cooperate with thefirst and second sections of the retainer to at least partially definethe first and second passages during movement of the first portion of asuture through the first passage and during movement of the secondportion of a suture through the second passage.
 13. A method as setforth in claim 12 wherein said step of decreasing the size of the firstand second passages includes decreasing the distance between the firstand second sections of the retainer.
 14. A method as set forth in claim13 wherein said step of decreasing the size of the first and secondpassages includes plastically deforming material of the plurality ofprojections.
 15. A method as set forth in claim 12 wherein a first oneof the projections of the plurality of projections is disposed betweenthe first and second portions of the suture when the first and secondportions of the suture are disposed in the first and second passages, asecond one of the projections of the plurality of projections isdisposed adjacent to one side of the first portion of the suture and athird one of the projections of the plurality of projections is disposedadjacent to one side of the second portion of the suture.
 16. A methodas set forth in claim 12 wherein said step of interconnecting the firstand second sections of the retainer includes deforming an end portion ofa first projection of the plurality of projections with the end portionof the first projection disposed in a recess formed in one of the firstand second sections of the retainer and deforming an end portion of asecond projection of the plurality of projections with the end portionof the second projection in a recess formed in one of the first andsecond sections of the retainer.
 17. A method as set forth in claim 12further including the step of transmitting force between the first andsecond sections of the retainer through the plurality of projectionswhile the first and second portions of the suture are disposed in thefirst and second passages.
 18. A method as set forth in claim 1 whereinsaid step of moving a first portion of the suture through a firstpassage includes sliding the first portion of the suture along a firstside of a projection disposed between the first and second sections ofthe retainer and said step of moving a second portion of the suturethrough the second passage includes sliding the second portion of thesuture along a second side of the projection disposed between the firstand second sections of the retainer.
 19. A method as set forth in claim18 further including the step of transmitting force between the firstand second sections of the suture retainer through the projection whilethe first and second portions of the suture are disposed in the firstand second passages.
 20. A method as set forth in claim 19 wherein saidstep of interconnecting the first and second sections of the retainerincludes plastically deforming material of the projection.
 21. A methodas set forth in claim 19 wherein said step of interconnecting the firstand second sections of the retainer includes bonding the projection toone of the first and second sections of the retainer.
 22. A method asset forth in claim 21 further including the steps of engaging a bottomportion of a first recess in the first section of the retainer with afirst projection from the second section of the retainer during movementof the first portion of the suture through the first passage, andengaging a bottom portion of a second recess in the first section of theretainer with a second projection from the second section of theretainer during movement of the second portion of the suture through thesecond passage.
 23. A method as set forth in claim 22 wherein said stepof interconnecting the first and second sections of the retainerincludes bonding the first projection with the bottom portion of thefirst recess and bonding the second projection with the bottom portionof the second recess.
 24. A method as set forth in claim 1 wherein saidstep of interconnecting the first and second sections of the retainerincludes applying ultrasonic vibratory energy to at least one of thefirst and second sections of the retainer.
 25. A method as set forth inclaim 1 further including the steps of engaging a surface area on thefirst section of the retainer with a pointed end portion of a firstprojection from the second section of the retainer and engaging asurface area on the first section of the retainer with a pointed endportion of a second projection from the second section of the retainer,said step of interconnecting the first and second sections of theretainer includes applying energy to the second section of the retainerand concentrating the energy applied to the second section of theretainer at the pointed end portions of the first and secondprojections.
 26. A method of securing a suture, said method comprisingthe steps of providing a retainer having a projection extending from afirst section of the retainer into a recess in a second section of theretainer, moving a portion of a suture between the first and secondsections of the retainer, and interconnecting the first and secondsections of the retainer with the portion of the suture at leastpartially disposed between the first and second sections of theretainer, said step of interconnecting the first and second sections ofthe retainer includes bonding an end portion of the projection extendingfrom the first section of the retainer to a bottom portion of a recessformed in the second section of the retainer.
 27. A method as set forthin claim 26 further including the step of moving a second portion of thesuture between the first and second sections of the retainer, said stepof interconnecting the first and sections of the retainer is performedwith the second portion of the suture at least partially disposedbetween the first and second sections of the retainer.
 28. A method asset forth in claim 26 wherein said step of interconnecting the first andsecond sections of the retainer includes decreasing a space betweenportions of the first and second sections of the retainer and applyingenergy to at least one of the first and second sections of the retainer.29. A method as set forth in claim 26 wherein said step ofinterconnecting the first and second sections of the retainer includesbonding an end portion of a second projection extending from the firstsection of the retainer to a bottom portion of a second recess formed inthe second section of the retainer.
 30. A method as set forth in claim26 further including the step of providing an interference fit betweenthe projection extending from the first section of the retainer and therecess formed in the second section of the retainer to maintain thefirst and second sections of the retainer in a desired spatialrelationship.
 31. A method as set forth in claim 26 further includingthe steps of gripping the retainer with an applicator assembly, andsliding the retainer along the suture while gripping the retainer withthe applicator assembly.
 32. A method as set forth in claim 31 whereinsaid step of bonding the end portion of the projection to the bottomportion of the recess includes transmitting energy from the applicatorassembly to the retainer.
 33. A method a set forth in claim 32 whereinsaid step of gripping the retainer includes gripping the retainer with apredetermined force and maintaining the force with which the retainer isgripped at least substantially constant during performance of said stepsof sliding the retainer along the suture and transmitting energy fromthe applicator assembly to the retainer.
 34. A method as set forth inclaim 26 further including the step of forming a loop in the suturearound the projection.
 35. A method as set forth in claim 26 whereinsaid step of interconnecting the first and second sections of theretainer includes applying energy to the first section of the retainerand concentrating the energy at the end portion of the projection.
 36. Amethod of securing a suture, said method comprising the steps ofpositioning first and second portions of a suture between first andsecond sections of a retainer, gripping the retainer with an applicatorassembly, sliding the retainer along the first and second portions ofthe suture while gripping the retainer with the applicator assembly, andinterconnecting the first and second sections of the retainer byapplying energy to, at least one of the first and second sections of theretainer with applicator assembly while gripping the retainer with theapplicator assembly and while the first and second portions of thesuture are at least partially disposed between the first and secondsections of the retainer.
 37. A method as set forth in claim 36 whereinsaid step of positioning first and second portions of the suture betweenfirst and second sections of a retainer includes moving the firstportion of the suture through a first passage which extends between thefirst and second sections of the retainer and moving the second portionof the suture through a second passage which extends between the firstand second sections of the retainer, said step of interconnecting thefirst and second sections of the retainer includes decreasing size ofthe first and second passages.
 38. A method as set forth in claim 36wherein said step of interconnecting the first and second sections ofthe retainer includes bonding end portions of projections extending fromthe one of the first and second sections of the retainer to bottomportions of recesses formed in another of the first and second sectionsof the retainer.
 39. A method as set forth in claim 36 further includingthe step of providing an interference fit between portions of the firstand second sections of the retainer to maintain the first and secondsections of the retainer in a desired spatial relationship duringpositioning of the first and second portions of the suture between thefirst and second sections of the retainer.
 40. A method as set forth inclaim 36 wherein said step of applying energy to at least one of thefirst and second sections of the retainer with the applicator assemblyincludes engaging a recess formed in the first section of the retainerwith a first member which forms part of the applicator assembly,engaging the second section of the retainer with a second member whichforms part of the applicator assembly, and transmitting energy to theretainer through at least one of the first and second members.
 41. Amethod as set forth in claim 36 wherein said step of gripping theretainer includes gripping the retainer with a predetermined force andmaintaining the force with which the retainer is gripped at least,substantially constant during performance of said step of sliding theretainer along the first and second portions of the suture.
 42. A methodas set forth in claim 36 further including the step of engaging firstand second recesses in the first section of the retainer with first andsecond projections extending from the second section of the retainer toposition the second section of the retainer relative to the firstsection of the retainer during performance of said step of positioningthe first and second portions of the suture between the first and secondsections of the retainer.
 43. A method as set forth in claim 36 whereinsaid step of positioning first and second portions of a suture betweenfirst and second sections of the retainer includes moving the firstportion of the suture in a first direction relative to the first andsecond sections of the retainer, and moving the second portion of thesuture in a second direction relative to the first and second sectionsof the retainer.
 44. A method as set forth in claim 36 wherein aplurality of projections are disposed between the first and secondsections of the retainer and at least partially define first and secondpassages, said step of positioning first and second portions of a suturebetween first and second sections of a retainer includes moving thefirst portion of the suture into the first passage and moving the secondportion of the suture into the second passage.
 45. A method as set forthin claim 44 wherein said step of interconnecting the first and secondsections of the retainer includes plastically deforming material of atleast some of the projections.
 46. A method as set forth in claim 44wherein a first one of the projections of the plurality of projectionsis disposed between the first and second portions of the suture when thefirst and second portions of the suture are disposed between the firstand second sections of the retainer, a second one of the projections ofthe plurality of projections is disposed adjacent to one side of thefirst portion of the suture, and a third one of the projections of theplurality of projections is disposed adjacent to one side of the secondportion of the suture.
 47. A method as set forth in claim 44 whereinsaid step of interconnecting the first and second sections of theretainer includes plastically deforming an end portion of a firstprojection of the plurality of projections with the end portion of thefirst projection disposed in a recess formed in one of the first andsecond sections of the retainer and plastically deforming an end portionof a second projection of the plurality of projections with end portionof the second projection in a recess formed in one of the first andsecond sections of the retainer.
 48. A method as set forth in claim 44further including the step of transmitting force between the first andsecond sections of the retainer through the plurality of projectionswhile the first and second portions of the suture are disposed betweenthe first and second sections of the retainer.
 49. A method as set forthin claim 36 wherein said step of positioning first and second portionsof the suture between first and second sections of the retainer includessliding the first portion of the suture along a first side of aprojection disposed between the first and second sections of theretainer and sliding the second portion of the suture along a secondside of the projection disposed between the first and second sections ofthe retainer.
 50. A method as set forth in claim 49 further includingthe step of transmitting force between the first and second sections ofthe retainer through the projection while the first and second portionsof the suture are disposed between the first and second sections of theretainer.
 51. A method as set forth in claim 50 wherein said step ofinterconnecting the first and second sections of the retainer includesplastically deforming material of the projection.
 52. A method as setforth in claim 50 wherein said step of interconnecting the first andsecond sections of the retainer includes bonding the projection to oneof the first and second sections of the retainer.
 53. A method as setforth in claim 36 wherein said step of gripping the retainer with anapplicator assembly includes positioning the retainer between first andsecond members, and applying force against the retainer with the firstmember to press the retainer against the second member, said step ofapplying energy to the retainer includes transmitting ultrasonicvibratory energy from the second member to the retainer while the firstmember presses the retainer against the second member.
 54. A method aset forth in claim 36 wherein said step of gripping the retainer with anapplicator assembly includes gripping the retainer with a predeterminedforce, said step of sliding the retainer along the first and secondportions of the suture is performed while gripping the retainer with thepredetermined force, said step of applying energy to the retainer isperformed while gripping the retainer with the predetermined force. 55.A method as set forth in claim 36 further including the steps ofengaging a bottom portion of a first recess in the first section of theretainer with a first projection from the second section of the retainerduring sliding of the retainer along the first and second portions ofthe suture, and engaging a bottom portion of a second recess in thefirst section of the retainer with a second projection from the secondsection of the retainer during sliding of the retainer along the firstand second portions of the suture.
 56. A method as set forth in claim 55wherein said step of interconnecting the first and second sections ofthe retainer includes bonding the first projection with the bottomportion of the first recess and bonding the second projection with thebottom portion of the second recess.
 57. A method as set forth in claim36 further including the steps of engaging a surface area on the firstsection of the retainer with a pointed end portion of a first projectionfrom the second section of the retainer and engaging a surface area onthe first section of the retainer with a pointed end portion of a secondprojection from the second section of the retainer, said step ofinterconnecting the first and second sections of the retainer includesconcentrating energy applied to the retainer at the pointed end portionsof the first and second projections.
 58. A method of securing a suture,said method comprising the steps of providing a retainer having firstand second sections, said first and second sections of said retainerinclude a plurality of projections, moving a first portion of the suturerelative to the retainer along a path which extends between the firstand second sections of the retainer and between first and secondprojections of the plurality of projections, moving a second portion ofthe suture relative to the retainer along a path which extends betweenthe first and second sections of the retainer and between the secondprojection and a third projection of the plurality of projections, andinterconnecting the first and second sections of the retainer with thefirst portion of the suture disposed between the first and secondsections of the retainer and between the first and second projections,said step of interconnecting the first and second sections of theretainer being performed with the second portion of the suture disposedbetween the first and second sections of the retainer and between thesecond and third projections, said step of interconnecting the first andsecond sections of the retainer includes applying energy to at least oneof the first and second sections of the retainer.
 59. A method as setforth in claim 58 wherein said step of moving the first portion of thesuture along the path which extends between the first and secondsections of the retainer and between the first and second projections isperformed with the first projection extending into a first recess in thefirst section of the retainer, said step of moving the second portion ofthe suture along the path which extends between the first and secondsections of the retainer and between the second and third projections isperformed with the third projection extending into a second recess inthe first section of the retainer.
 60. A method as set forth in claim 59wherein said step of interconnecting the first and second sections ofthe retainer includes connecting an end portion of the first projectionto a bottom portion of the first recess and connecting an end portion ofthe second projection to a bottom portion of the second recess.
 61. Amethod as set forth in claim 59 further including the step of retainingthe first and second sections of the retainer in a desired spatialrelationship by transmitting force between surfaces of the first andthird projections and said first and second recesses during movement ofthe first portion of the suture along the path which extends between thefirst and second sections of the retainer and between the first andsecond projections and during movement of the second portion of thesuture along the path which extends between the first and secondsections of the retainer and between the second and third projections.62. A method as set forth in claim 59 wherein said step of moving thefirst portion of the suture along the path which extends between thefirst and second sections of the retainer and between the first andsecond projections and said step of moving the second portion of thesuture along the path which extends between the first and secondsections of the retainer and between the second and third projections isperformed with the second projection extending from the second sectionof the retainer toward the first section of the retainer.
 63. A methodas set forth in claim 62 wherein said step of interconnecting the firstand second sections of the retainer includes connecting an end portionof the third projection to the first section of the retainer.
 64. Amethod as set forth in claim 58 wherein said step of moving the firstportion of the suture along the path which extends between the first andsecond sections of the retainer and between the first and secondprojections includes moving the first portion of the suture betweengenerally parallel side surface areas disposed on the first and secondprojections to maintain the first portion of the suture in a desiredspatial relationship with the first and second sections of the retainer,said step of moving the second portion of the suture along the pathwhich extends between the first and second sections of the retainer andbetween the second and third projections includes moving the secondportion of the suture between generally parallel side surface areasdisposed on the second and third projections to maintain the secondportion of the suture in a desired spatial relationship with the firstand second sections of the retainer.
 65. A method as set forth in claim58 further including the steps of gripping the retainer with anapplicator assembly, and sliding the retainer along the first and secondportions of the suture while gripping the retainer with the applicatorassembly, said step of interconnecting the first and second sections ofthe retainer is at least partially performed while gripping the retainerwith the applicator assembly.
 66. A method as set forth in claim 58wherein said step of moving a first portion of the suture along a pathwhich extends between the first and second projections is performed witha pointed end portion of the first projection engaging a surface area onthe first section of the retainer, said step of moving a second portionof the suture along a path which extends between second and thirdprojections is performed with a pointed end portion of the thirdprojection engaging a surface area on the first section of the retainer.67. A method as set forth in claim 66 wherein said step ofinterconnecting the first and second sections of the retainer includesconcentrating energy applied to the retainer at the pointed end portionsof the first and third projections.
 68. A method as set forth in claim58 wherein said step of moving a first portion of the suture along apath which extends between the first and second projections is performedwith the first projection extending from the second section of theretainer into engagement with a surface area on the first section of theretainer and with second projection extending from the first section ofthe retainer to a location adjacent to and spaced from the secondsection of the retainer, said step of moving a second portion of thesuture along a path which extends between the second and thirdprojections is performed with the second projection extending from thefirst section of the retainer to a location adjacent to and spaced fromthe second section of the retainer and with the third projectionextending from the second section of the retainer into engagement with asurface area on the first section of the retainer.
 69. An apparatus foruse in securing a suture, said apparatus comprising a first retainersection, and a second retainer section, said first retainer sectionhaving first and second projections which extend into first and secondrecesses in said second retainer section, said first and second retainersections and said first and second projections at least partially definea first passage which receives a first portion of the suture and asecond passage which receives a second portion of the suture.
 70. Anapparatus as set forth in claim 69 wherein said second retainer sectionhas a third projection which extends from said second retainer sectionand cooperates with said first and second projections to at leastpartially define the first and second passages.
 71. An apparatus as setforth in claim 69 wherein said first projection has an end portion whichengages a bottom portion of the first recess and said second projectionhas an end portion which engages a bottom portion of the second recess.72. An apparatus as set forth in claim 69 wherein said first projectionhas an interference fit with the first recess and said second projectionhas an interference fit with the second recess to maintain said firstand second retainer sections in a desired spatial relationship duringmovement of the first portion of the suture into the first passage andduring movement of the second portion of the suture into the secondpassage.
 73. An apparatus as set forth in claim 69 wherein said firstprojection has a flat side surface area which faces toward said secondprojection and at least partially defines the first passage and saidsecond projection has a flat side surface area which faces toward saidfirst projection and at least partially defines the second passage. 74.An apparatus as set forth in claim 73 further including a thirdprojection which is disposed between said first and second projections,said third projection having a flat side surface area which faces towardsaid first projection and at least partially defines the first passageand a flat side surface area which faces toward said second projectionand at least partially defines the second passage.
 75. An apparatus asset forth in claim 74 wherein said flat side surface areas on said thirdprojection extend parallel to the flat side surface area on said firstprojection and to the flat side surface area on said second projection.76. An apparatus as set forth in claim 74 wherein said third projectionextends from said second retainer section toward said first retainersection.
 77. An apparatus as set forth in claim 74 wherein said secondretainer section includes a groove which faces away from said firstretainer section and receives a force application member during anapplication of energy to said first retainer section to effect a bondingof said first and second projections to said second retainer section.78. An apparatus as set forth in claim 69 wherein said first recess hasparallel side surfaces which are interconnected by a bottom surface,said first projection having parallel side surfaces which are disposedin engagement with said parallel side surfaces of said first recess anda pointed end portion disposed adjacent to said bottom surface of saidfirst recess, said second recess having parallel side surfaces which areinterconnected by a bottom surface, said second projection havingparallel side surfaces which are disposed in engagement with saidparallel side surfaces of said second recess and a pointed end portionwhich is disposed adjacent to said bottom surface of said second recess.79. An apparatus as set forth in claim 69 further including a thirdprojection extending from said second retainer section toward said firstretainer section, said third projection having side surfaces whichextend parallel to said side surfaces of said first recess and to saidside surfaces of said second recess.
 80. An apparatus as set forth inclaim 69 wherein said first and second recesses have an elongatedconfiguration, said first projection having an end portion which is atleast partially defined by first and second planes which intersect alonga line parallel to a longitudinal central axis of said first recess,said second projection having an end portion which is at least partiallydefined by third and fourth planes which intersect along a line parallelto a longitudinal central axis of said second recess.
 81. An apparatusas set forth in claim 80 wherein said end portion of said firstprojection is disposed in engagement with a bottom of said first recessand said end portion of said second projection is disposed in engagementwith a bottom of said second recess.
 82. An apparatus as set forth inclaim 69 wherein said first retainer section includes a circular bodyfrom which said first and second projections extend, said secondretainer section having a circular body in which said first and secondrecesses are disposed, said first and second projections being spacedequal distances from a central axis of said circular body of said firstretainer section, said circular body of said second retainer sectionhaving a central axis which is coincident with the central axis of saidcircular body of said first retainer section.
 83. An apparatus for usein securing a suture, said apparatus comprising a first retainersection, and a second retainer section, said first retainer sectionhaving a first projection with an end portion which engages a firstbonding surface area on said second retainer section, said firstretainer section having a second projection with an end portion whichengages a second bonding surface area on said second retainer section,said end portion of said first projection being at least partiallydefined by flat surfaces which are disposed in planes which intersectalong a first line which extends along said first bonding surface areaon said second retainer section, said end portion of said secondprojection being partially defined flat surfaces which are disposed inplanes which intersect along a second line which extends along saidsecond bonding surface area on said second retainer section, a firstgripper surface area on said first retainer section adjacent to saidfirst projection, said first gripper surface area being disposed on saidfirst retainer section at a location between said first and secondprojections, a second gripper surface area on said second retainersection, said first and second gripper surface areas cooperating toapply force against a first portion of the suture, a third grippersurface area on said first retainer section adjacent to said secondprojection, said third gripper surface area being disposed on said firstretainer section at a location between said first and secondprojections, a fourth gripper surface are on said second retainersection, said third and fourth gripper surface areas cooperating toapply force against a second portion of the suture, said first andsecond retainer sections having outer side surface areas against whichforce is applied to press said first and second gripper surface areasagainst opposite sides of the first portion of the suture and to presssaid third and fourth surface areas against opposite sides of the secondportion of the suture, said outer side surface area on said firstretainer section being effective to receive energy which effects bondingof the end portion of the first projection with material of the secondretainer section at the first bonding surface area on the secondretainer section and which effects bonding of the end portion of thesecond projection with material of the second retainer section at thesecond bonding surface area on the second retainer section.
 84. Anapparatus as set forth in claim 83 wherein said second retainer sectionincludes a third projection which is at least partially disposed betweensaid first and second projections, said third projection having a firstside surface area which faces toward said first projection and isengagable by the first portion of the suture, said third projectionhaving a second side surface area which faces toward said secondprojection and is engagable by the second portion of the suture.
 85. Anapparatus as set forth in claim 83 wherein said second retainer sectionincludes first and second recesses, said first bonding surface areaforms at least a portion of a bottom of said first recess and saidsecond bonding surface area forms at least a portion of a bottom of saidsecond recess.
 86. An apparatus for use in securing a suture, saidapparatus comprising a manually engagable handle portion, a housingconnected with said handle portion, an elongated energy transmissionmember extending from said housing and having a first end portion andconnectable with a source of energy, said elongated energy transmissionmember having a second end portion which is engagable with a first sideof a suture retainer, an elongated tubular force transmission member atleast partially enclosing said elongated energy transmission member, anda biasing spring assembly at least partially enclosed within saidhousing and operable to provide force which is transmitted to a firstend portion of said elongated tubular force transmission member, saidelongated tubular force transmission member having a second end portionwhich is pressed against a second side of the suture retainer to gripthe suture retainer between said second end portion of said elongatedenergy transmission member and said second end portion of said elongatedtubular force transmission member during transmission of energy from thesource of energy through said elongated energy transmission member tothe suture retainer.
 87. An apparatus for use in securing a suture, saidapparatus comprising a first retainer section, and a second retainersection, a first surface area on said first retainer section having aninterference fit with a first surface area on said second retainersection, a second surface area on said first retainer section having aninterference fit with a second surface area on said second retainersection, said first and second retainer sections cooperating to receivefirst and second portions of a suture while the interferences fitsbetween surface areas on said first and second retainer sectionsmaintain said first and second retainer sections in a desired spatialrelationship, said first and second retainer sections having outer sidesurface areas against which force is applied to press said first andsecond retainer sections against the first portion of the suture and thesecond portion of the suture, said outer side surface area on at leastone of said first and second retainer sections being effective toreceive energy which effects bonding of the first and second retainersections together.
 88. An apparatus as set forth in claim 87 whereinsaid first retainer section has a first projection which extends into afirst recess in said second retainer section, said first retainersection has a second projection which extends into a second recess insaid second retainer section, said first and second projections beingheld in said first and second recesses by the interference fits betweensurface areas on said first and second retainer sections.
 89. Anapparatus as set forth in claim 88 wherein said first surface area onsaid first retainer section is disposed on said first projection andsaid first surface area on said second retainer section is disposed insaid first recess, said second surface area on said first retainersection is disposed on said second projection and said second surfacearea on said second retainer section is disposed in said second recess.90. An apparatus as set forth in claim 88 wherein said first and secondsurface areas on said first retainer section are disposed on said firstprojection and said first and second surface areas on second retainersection are disposed in said first recess.
 91. A method of securing asuture, said method comprising the steps of moving a first portion ofthe suture between first and second sections of a retainer, moving asecond portion of the suture between the first and second sections ofthe retainer, maintaining the first and second retainer sections in adesired spatial relationship under the influence of interference fitbetween surfaces on the first and second sections of the retainer duringperformance of said steps of moving the first portion of the suturebetween the first and second sections of the retainer and moving thesecond portion of the suture between the first and second sections ofthe retainer, and interconnecting the first and second sections of theretainer with the first and second portions of the suture at leastpartially disposed between the first and second sections of theretainer.
 92. A method as set forth in claim 91 wherein said step ofinterconnecting the first and second sections of the retainer includesbonding an end portion of a projection extending from the first sectionof the retainer to a surface of a recess in the second section of theretainer.
 93. A method as set forth in claim 92 wherein the interferencefit is established between a surface on the projection from the firstsection of the retainer and a surface of the recess in the secondsection of the retainer.
 94. A method as set forth in claim 91 whereinsaid step of interconnecting the first and second sections of theretainer includes bonding an end portion of a first projection from thefirst section of the retainer to a bottom portion of a first recess inthe second section of the retainer and bonding an end portion of asecond projection from the first section of the retainer to a bottomportion of a second recess in the second section of the retainer.
 95. Amethod as set forth in claim 94 wherein the interference fit is providedbetween a surface on the first projection from the first section of theretainer and a surface of the first recess in the second section of theretainer and is provided between a surface on the second projection fromthe first section of the retainer and a surface of the second recess inthe second section of the retainer.
 96. A method as set forth in claim91 wherein said step of interconnecting the first and second sections ofthe retainer includes decreasing the size of space in which the firstand second portions of the suture are disposed and applying energy to atleast one of the first and second sections of the retainer.
 97. A methodas set forth in claim 91 wherein said step of interconnecting the firstand second sections of the retainer includes changing the spatialrelationship between the first and second sections of the retainer andeffecting relative movement between the surfaces on the first and secondsections of the retainer where the interference fit is established. 98.A method as set forth in claim 91 further including the steps ofgripping the retainer with an applicator assembly, and sliding theretainer along the first and second portions of the suture whilegripping the retainer with the applicator assembly.
 99. A method as setforth in claim 91 wherein said step of interconnecting the first andsecond sections of the retainer includes bonding an end portion of aprojection from the first section of the retainer to a bottom portion ofa recess formed in the second section of the retainer.
 100. A method asset forth in claim 91 wherein said step of moving the first portion ofthe suture between the first and second sections of the retainerincludes moving the first portion of the suture into a first passageformed between the first and second sections of the retainer, said stepof moving the second portion of the suture between the first and secondsections of the retainer includes moving the second portion of thesuture between the first and second sections of the retainer.
 101. Amethod of securing a suture, said method comprising the steps ofpositioning first and second portions of a suture between first andsecond sections of a retainer with end portions of a plurality ofprojections from the first retainer section disposed in engagement withsurface areas on the second retainer section, sliding the retainer alongthe first and second portions of the suture with the end portions of theprojections from the first retainer section disposed in engagement withthe surface areas on the second retainer section, and, interconnectingthe first and second sections of the retainer by applying energy to theretainer and bonding the end portions of the projections from the firstretainer section to the second retainer section.
 102. A method as setforth in claim 101 wherein said step of interconnecting the first andsecond sections of the retainer includes concentrating the energyapplied to the retainer with pointed end portions of the projections.103. A method as set forth in claim 101 wherein said step of sliding theretainer along the first and second portions of the suture includesmoving the retainer into a cannula.
 104. A method as set forth in claim101 further including the step of gripping the retainer with anapplicator assembly, said step of sliding the retainer along the firstand second portions of the suture includes moving the retainer into acannula while gripping the retainer with the applicator assembly.
 105. Amethod as set forth in claim 104 wherein said step of interconnectingthe first and second sections of the retainer by applying energy to theretainer includes transmitting energy from the applicator assembly tothe retainer while gripping the retainer.
 106. A method as set forth inclaim 104 wherein said step of gripping the retainer with the applicatorassembly includes gripping the retainer with a predetermined force. 107.A method as set forth in claim 106 wherein said step of transmittingenergy from the applicator assembly to the retainer is performed whilegripping the retainer with the predetermined force.
 108. A method as setforth in claim 101 further including the steps of moving the retainerinto a cannula, and moving a portion of an applicator assembly into thecannula, said step of applying energy to the retainer and bonding theend portions of the projections from the first retainer section to thesecond retainer section includes transmitting energy from the applicatorassembly to the retainer while the applicator assembly extends into thecannula.
 109. A method as set forth in claim 101 wherein said step ofpositioning first and second portions of the suture between first andsecond sections of the retainer includes moving the first portion of thesuture through a first passage which extends between the first andsecond sections of the retainer and moving the second portion of thesuture through a second passage which extends between the first andsecond sections of the retainer.
 110. A method as set forth in claim 101further including the step of providing an interference fit between theplurality of projections from the first retainer section and the surfaceareas on the second retainer section.
 111. A method as set forth inclaim 101 further including the steps of engaging a first recess in thesecond retainer section with a first projection of the plurality ofprojections from the first retainer section during performance of saidstep of sliding the retainer along the first and second portions of thesuture and engaging a second recess in the second retainer section witha second projection of the plurality of projections from the firstretainer section during performance of said step of sliding the retaineralong the first and second portions of the suture.
 112. A method as setforth in claim 101 further including the steps of forming a first loopin the first portion of the suture around a first projection of theplurality of projections and forming a second loop in the second portionof the suture around a second projection of the plurality ofprojections, said step of sliding the retainer along the first andsecond portions of the suture includes moving the first loop along thefirst portion of the suture and moving the second loop along the secondportion of the, suture.
 113. A method as set forth in claim 101 whereinsaid step of interconnecting the first and second sections of theretainer includes deforming an end portion of a first projection of theplurality of projections with the end portion of the first projectiondisposed in a first recess in the second retainer section and deformingan end portion of a second projection of the plurality of projectionswith the end portion of the second projection in a second recess in thesecond retainer section.
 114. A method as set forth in claim 101 whereinsaid step of sliding the retainer along the first and second portions ofthe suture includes moving the first portion of the suture relative tothe retainer along a path which extends between first and secondprojections of the plurality of projections and moving the secondportion of the suture relative to the retainer along a path whichextends between the second projection, and a third projection of theplurality of projections.
 115. A method as set forth in claim 101wherein said step of sliding the retainer along the first and secondportions of the suture include moving the first portion of the suturerelative to the retainer in a first direction along a path which extendsbetween first and second projections of the plurality of projections andmoving the second portion of the suture relative to the retainer in asecond direction which is opposite to the first direction along a pathwhich extends between the first and second projections of the pluralityof projections.
 116. A method as set forth in claim 115 wherein a thirdprojection of the plurality of projections is disposed between the firstand second projections and between the paths along which the first andsecond portions of the suture move relative to the retainer.
 117. Amethod as set forth in claim 115 wherein the first and second portionsof the suture and the paths along which the first and second portions ofthe suture move relative to the retainer are disposed in a side-by-siderelationship in the retainer.
 118. A method of securing a suture, saidmethod comprising the steps of positioning a cannula relative to tissuein a patient's body, moving at least a portion of a suture through thecannula into the patient's body, moving a portion of an applicatorassembly into the cannula, positioning the suture between first andsecond sections of a retainer, gripping the retainer with the applicatorassembly, sliding the retainer along the suture while the retainer isgripped by the applicator assembly, and, thereafter, interconnecting thefirst and second sections of the retainer by applying energy to at leastone of the first and second sections of the retainer with the applicatorassembly while a portion of the applicator assembly is disposed in thecannula.
 119. A method as set forth in claim 118 wherein said step ofpositioning the suture between the first and second sections of theretainer includes moving a first portion of the suture through a firstpassage which extends between the first and second sections of theretainer and moving a second portion of the suture through a secondpassage which extends between the first and second sections of theretainer.
 120. A method as set forth in claim 119 wherein said step ofinterconnecting the first and second sections of the retainer includesdecreasing size of the first and second passages.
 121. A method as setforth in claim 118 wherein said step of interconnecting the first andsecond sections of the retainer includes bonding an end portion of aprojection extending from the first section of the retainer to a bottomportion of a recess formed in the second section of the retainer.
 122. Amethod as set forth in claim 118 wherein said step of positioning thesuture between first and second sections of the retainer includespositioning first and second portions of the suture between the firstand second sections of the retainer, said step of sliding the retaineralong the suture includes sliding the retainer along the first andsecond portions of the suture.
 123. A method as set forth in claim 118further including the step of maintaining the first and second sectionsof the retainer in a desired spatial relationship with each other underthe influence of an interference fit between surfaces on the first andsecond sections of the retainer during performance of said step ofsliding the retainer along the suture.
 124. A method as set forth inclaim 118 wherein said step of positioning the suture between first andsecond sections of the retainer is performed prior to performance ofsaid step of moving a portion of the applicator assembly into thecannula.
 125. A method as set forth in claim 118 wherein said step ofpositioning the suture between first and second sections of the retaineris performed after performance of said step of moving a portion of theretainer into the cannula.
 126. A method as set forth in claim 118wherein said step of gripping the retainer with the applicator assemblyis at least partially performed while the retainer is outside thepatient's body.
 127. A method as set forth in claim 118 wherein said sepof gripping the retainer with the applicator assembly is at leastpartially performed while the retainer is inside the patient's body.128. A method as set forth in claim 118 further including the step oftensioning the suture while sliding the retainer along the suture. 129.A method as set forth in claim 118 wherein said sep of gripping theretainer with the applicator assembly includes gripping the retainerwith a predetermined force, said step of sliding the retainer along thesuture while the retainer is gripped by the applicator assembly includesgripping the retainer with the predetermined force, said step ofinterconnecting the first and second sections of the retainer includesgripping the retainer with the predetermined force.
 130. A method as setforth in claim 118 wherein said sep of applying energy to the retainerwith the applicator assembly includes applying ultrasonic vibratoryenergy to the retainer.
 131. A method of securing a suture, said methodcomprising the steps of positioning first and second portions of asuture between first and second sections of a retainer with end portionsof a plurality of projections from the first retainer section disposedin engagement with surface areas on the second retainer section, and,interconnecting the first and second sections of the retainer byapplying energy to the retainer and bonding the end portions of theprojections from the first retainer section to the second retainersection, said step of interconnecting the first and second sections ofthe retainer includes concentrating the energy applied to the retainerat the end portions of the projections and deforming the end portions ofthe projections.
 132. A method as set forth in claim 131 wherein saidstep of concentrating the energy applied to the retainer includesconcentrating the energy at pointed end portions of the projections.133. A method as set forth in claim 131 further including the slidingthe retainer along the first and second portions of the suture.
 134. Amethod as set forth in claim 131 further including the step of grippingthe retainer with an applicator assembly and sliding the retainer alongthe first and second portions of the suture while gripping the retainerwith the applicator assembly.
 135. A method as set forth in claim 134wherein said step of interconnecting the first and second sections ofthe retainer by applying energy to the retainer includes transmittingenergy from the applicator assembly to the retainer while gripping theretainer.
 136. A method as set forth in claim 135 wherein said step ofgripping the retainer with the applicator assembly includes gripping theretainer with a predetermined force.
 137. A method as set forth in claim136 wherein said step of transmitting energy from the applicatorassembly to the retainer is performed while gripping the retainer withthe predetermined force.
 138. A method as set forth in claim 131 furtherincluding the steps of moving the retainer into a cannula, and moving aportion of an applicator assembly into the cannula, said step ofapplying energy to the retainer and bonding the end portions of theprojections from the first retainer section to the second retainersection includes transmitting energy from the applicator assembly to theretainer while the applicator assembly extends into the cannula.
 139. Amethod as set forth in claim 131 wherein said step of positioning firstand second portions of the suture between first and second sections ofthe retainer includes moving the first portion of the suture through afirst passage which extends between the first and second sections of theretainer and moving the second portion of the suture through a secondpassage which extends between the first and second sections of theretainer.
 140. A method as set forth in claim 131 further including-thestep of providing an interference fit between the plurality ofprojections from the first retainer section and the surface areas on thesecond retainer section.
 141. A method as set forth in claim 131 furtherincluding the steps of engaging a first recess in the second retainersection with a first projection of the plurality of projections from thefirst retainer section and engaging a second recess in the secondretainer section with a second projection of the plurality ofprojections from the first retainer, said step of interconnecting thefirst and second retainer sections being performed with the firstprojection extending into the first recess and with the secondprojection extending into the second recess.
 142. A method as set forthin claim 131 further including the steps of forming a first loop in thefirst portion of the suture around a first projection of the pluralityof projections and forming a second loop in the second portion of thesuture around a second projection of the plurality of projections. 143.A method as set forth in claim 131 wherein said step of interconnectingthe first and second sections of the retainer includes deforming an endportion of a first projection of the plurality of projections with theend portion of the first projection disposed in a first recess in thesecond retainer section and deforming an end portion of a secondprojection of the plurality of projections with the end portion of thesecond projection in a second recess in the second retainer section.144. A method as set forth in claim 131 further including the steps ofmoving the first portion of the suture relative to the retainer along apath which extends between first and second projections of the pluralityof projections and moving the second portion of the suture relative tothe retainer along a path which extends between the second projectionand a third projection of the plurality of projections.
 145. A method asset forth in claim 131 further including the steps of moving the firstportion of the suture relative to the retainer in a first directionalong a path which extends between first and second projections of theplurality of projections and moving the second portion of the suturerelative to the retainer in a second direction which is opposite to thefirst direction along a path which extends between the first and secondprojections of the plurality of projections.
 146. A method as set forthin claim 145 wherein a third projection of the plurality of projectionsis disposed between the first and second projections and between thepaths along which the first and second portions of the suture moverelative to the retainer.
 147. A method as set forth in claim 145wherein the first and second portions of the suture and the paths alongwhich the first and second portions of the suture move relative to theretainer are disposed in a side-by-side relationship in the retainer.148. A method of securing a suture, said method comprising the steps ofpositioning first and second portions of a suture between first andsecond sections of a retainer with portions of a plurality ofprojections from the first retainer section disposed in engagement withsurface areas on the second retainer, said step of positioning first andsecond portions of the suture between first and second sections of theretainer includes forming a first loop in the first portion of thesuture around a first projection of the plurality of projections andforming a second loop in the second portion of the suture around asecond projection of the plurality of projections, and, interconnectingthe first and second sections of the retainer by applying energy to theretainer and bonding portions of the projections from the first retainersection to the second retainer section.
 149. A method as set forth inclaim 148 wherein said step of interconnecting the first and secondsections of the retainer includes concentrating the energy applied tothe retainer with pointed end portions of the projections.
 150. A methodas set forth in claim 148 further including the steps of sliding theretainer along the first and second portions of the suture and movingthe first and second loops along the first and second portions of thesuture as the retainer slides along the first and second portions of thesuture.
 151. A method as set forth in claim 148 further including thesteps of gripping the retainer with an applicator assembly and movingthe retainer into a cannula while gripping the retainer with theapplicator assembly.
 152. A method as set forth in claim 151 whereinsaid step of interconnecting the first and second sections of theretainer by applying energy to the retainer includes transmitting energyfrom the applicator assembly to the retainer while gripping theretainer.
 153. A method as set forth in claim 151 wherein said step ofgripping the retainer with the applicator assembly includes gripping theretainer with a predetermined force.
 154. A method as set forth in claim153 wherein said step of transmitting energy from the applicatorassembly to the retainer is performed while gripping the retainer withthe predetermined force.
 155. A method as set forth in claim 148 whereinsaid step of positioning first and second portions of the suture betweenfirst and second sections of the retainer includes moving the firstportion of the suture through a first passage which extends between thefirst and second sections of the retainer and moving the second portionof the suture through a second passage which extends between the firstand second sections of the retainer.
 156. A method as set forth in claim148 further including the step of providing an interference fit betweenthe plurality of projections from the first retainer section and thesurface areas on the second retainer section.
 157. A method as set forthin claim 148 further including the steps of engaging a first recess inthe second retainer section with a first projection of the plurality ofprojections from the first retainer section and engaging a second recessin the second retainer section with a second projection of the pluralityof projections from the first retainer section.
 158. A method as setforth in claim 148 wherein said step of interconnecting the first andsecond sections of the retainer includes deforming an end portion of afirst projection of the plurality of projections with the end portion ofthe first projection disposed in a first recess in the second retainersection and deforming and portion of a second projection of theplurality of projections with the end portion of the second projectionin a second recess in the second retainer section.